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OpenAdvisories

Weakness (CWE)

CWE-193: Off-by-one Error

Base Draft

A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

How to prevent it (1 mitigation)
  1. Implementation

    When copying character arrays or using character manipulation methods, the correct size parameter must be used to account for the null terminator that needs to be added at the end of the array. Some examples of functions susceptible to this weakness in C include strcpy(), strncpy(), strcat(), strncat(), printf(), sprintf(), scanf() and sscanf().

Source: MITRE CWE-193

78 results · Clear filters · Feed

  • Medium 6.5

    Microsoft Office Word Information Disclosure Vulnerability

    Off-by-one error in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.

  • Medium 5.5

    Windows Container Isolation FS Filter Driver (unionfs.sys) Elevation of Privilege Vulnerability

    Off-by-one error in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.

  • Medium 5.1

    Off-by-one error in the MigTD's vmcall_raw transport for the Intel(R) TDX Migration Trust Domain (MigTD) within Ring 0:…

  • Medium 5.3

    An off-by-one error in certain ASUS Router firmware allows an unauthenticated nearby user to send a packet with a speci…

  • Medium 5.1

    compose-lint: `fix --apply` can delete a line the user did not select, including a security setting

    compose-lint is a Docker Compose security linter that identifies dangerous misconfigurations before deployment. From 0.9.0 until 0.18.0, compose-lint's YAML parser recognizes lone carriage returns and Unicode line separators U+0085, U+2028, and U+2029 as line…

  • Medium 5.3

    FreeSWITCH: Pre-authentication out-of-bounds writes in mod_xml_rpc WebSocket frame parsing

    FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to 1.11.2, ws_read_frame() unmasked a WebSocket payload by iterating w…

  • Medium 5.9

    FreeSWITCH: Off-by-one heap write in core XML serialization of four-byte UTF-8 sequences

    FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to 1.11.2, switch_xml_ampencode() reserved only ten bytes for the wide…

  • Medium 6.1

    libpff through 20260926 Heap Out-of-Bounds Read via libpff_table_read_6c_record_entries

    libpff through 20260926 contains an off-by-one bounds check in libpff_table_read_6c_record_entries that allows attackers to trigger a heap out-of-bounds read via crafted 6c table record entries. Attackers can supply crafted PST, OST or PAB files to applicatio…

  • Medium 6.5

    vLLM: Out-of-vocabulary prompt token id passes input validation and triggers a CUDA device-side assert (engine crash / DoS)

    vLLM is an inference and serving engine for large language models. Prior to 0.32.0, vllm/tokenizers/hf.py computes max_token_id with an off-by-one upper bound, allowing a pre-tokenized prompt ID equal to the vocabulary size to pass validation. For a tensor-pa…

  • Medium 5.3

    Mod_qos: query truncation during json body merging permits security-rule bypass

    A flaw was found in mod_qos. An off-by-one pointer calculation error occurs when merging request body parameters with an existing URL query, which truncates the query string during security evaluation while leaving the actual request unchanged. An unauthentic…

  • Medium 4.3

    IBM MQ Buffer Overflow

    IBM MQ could allow an authenticated attacker to cause potential process instability due to an off-by-one buffer overflow when processing specially crafted object names.

  • Medium 6.1

    unarr through 1.1.1 Off-by-One Heap Buffer Overflow via tar_get_name

    unarr through 1.1.1 contains an off-by-one heap-based buffer overflow in tar_get_name() in tar/parse-tar.c, reachable through the ar_entry_get_name() API. Attackers can supply a crafted TAR archive with a full ustar prefix and name to write a NUL byte past th…

  • Medium 6.5

    Remote DoS via receive-side kernel TLS

    TLS 1.3 embeds the actual record type as the last non-zero byte of the decrypted payload, optionally followed by zero padding. The code which searches for the inner record type had an off-by-one bug which could be triggered by an invalid frame, leading to an …

  • Medium 5.8

    OWASP Coraza WAF: jsDecode Off-by-One in Octal Escape Handling Enables WAF Bypass

    OWASP Coraza WAF is a golang modsecurity compatible web application firewall library. From 3.0.0 until 3.8.0, the t:jsDecode transformation in internal/transformations/js_decode.go:64-70 includes the backslash in the octal buffer, causing ParseInt to fail and…

  • Medium 5.3

    wstrncat() unsigned integer underflow leads to an off-by-one null write in wolfSSH on non-Windows platforms

    Unsigned integer underflow in wstrncat() in src/port.c in wolfSSL wolfSSH from v1.4.11 through v1.5.0 on non-Windows platforms allows an authenticated remote attacker to write one out-of-bounds null byte past the end of a stack buffer by sending a crafted SFT…

  • Medium 5.4

    Sssd: sssd: access control bypass via improper ldap shadow expiration check

    A flaw was found in SSSD. When configured to enforce account expiration using LDAP (Lightweight Directory Access Protocol) shadow attributes, SSSD fails to treat an expiration value of zero as an expired account. A user with valid credentials for an expired a…

  • Medium 5.3

    DHCP client option walk drifts one byte per skipped option, reading past the received message and past the saved options buffer

    In Eclipse ThreadX NetX Duo versions 6.0 through 6.5.2.202603a, the DHCP client's option walk advances its offset one byte less than its read pointer for every option it skips. A DHCP server, or any host on the link that answers first, can make the client rea…

  • Medium 6.9

    Off-by-one Error, Out-of-bounds Write vulnerability in RTI Connext Professional (Core Libraries) allows Overflow Buffers.

    Off-by-one Error, Out-of-bounds Write vulnerability in RTI Connext Professional (Core Libraries) allows Overflow Buffers. This issue affects Connext Professional: from 7.4.0 before 7.7.0.1, from 7.0.0 before 7.3.1.6.

  • Medium 6.5

    Netdata: Streaming protocol chart slot guard off-by-one allows ~16 GiB allocation request, crashing parent agent

    Netdata is an open source observability tool. Prior to 2.10.4, an authenticated child agent can send an oversized CHART SLOT value that str2ull_encoded passes to pluginsd_rrdset_cache_put_to_slot in src/plugins.d/pluginsd_internals.h. The accepted slot drives…

  • Medium 5.5

    Imager versions before 1.036 for Perl disclose uninitialised heap memory reading a paletted image with pixel indexes past its colour map in i_gpix_p and i_glin_p

    Imager versions before 1.036 for Perl disclose uninitialised heap memory reading a paletted image with pixel indexes past its colour map in i_gpix_p and i_glin_p. The palette is allocated uninitialised, and only the entries a reader adds count as populated. T…

  • Medium 6.5

    snappy-java through 1.1.10.8 Buffer Overflow via typed uncompress methods

    snappy-java through 1.1.10.8 contains a buffer overflow vulnerability in typed Snappy.uncompress*Array methods that allocate output arrays by dividing uncompressed length by element size but pass the undivided length to native code. Attackers controlling comp…

  • Medium 5.5

    ZITADEL: Improper Role Revocation on Granted Projects during Multiple Role Deletions

    ZITADEL is an open source identity management platform. Prior to version 4.16.0, a bug in how ZITADEL updates permissions when multiple project roles are deleted at the same time can cause some user permissions to be missed. This issue specifically affects Us…

  • Medium 4.4
    CVE-2026-90781 Public exploit

    alsa-lib through 1.2.16.1 Off-by-One Stack Buffer Overflow in __snd_ctl_ascii_elem_id_parse()

    alsa-lib through 1.2.16.1 contains a stack buffer overflow in the __snd_ctl_ascii_elem_id_parse() function that writes one byte past a 64-byte buffer when parsing a name= field with 64 or more characters. Attackers can supply a long control-element identifier…

  • Medium 5.5

    Win32k Information Disclosure Vulnerability

    Out-of-bounds read in Windows Win32K allows an authorized attacker to disclose information locally.

  • Medium 6.9

    PJSIP: SIP message header buffer overflow

    PJSIP is a free and open source multimedia communication library written in C. Prior to commit d6a0e7f, a buffer overflow can occur in pjsip_generic_array_hdr_print() in pjsip/src/pjsip/sip_msg.c, the function that serializes generic array headers (such as Al…

  • Medium 6.1

    MOOS core-moos through 10.4.0 Off-by-One Buffer Overflow in Serial Telegram Handling

    MOOS core-moos through 10.4.0 contains a buffer overflow vulnerability in CMOOSSerialPort::GetTelegram() that writes a NUL terminator one byte past the serial telegram stack buffer. Attackers controlling the serial line can send a full-length telegram to trig…

  • Medium 5.4

    Off-by-one out-of-bounds NUL write in Zephyr LwM2M JSON string parser

    The LwM2M JSON content formatter's get_string() in subsys/net/lib/lwm2m/lwm2m_rw_json.c copies a parsed JSON string into a caller-supplied buffer and NUL-terminates it. The length guard used if (string_length > buflen), which accepts a string whose length is …

  • Medium 6.1

    hashcat through 7.1.2 Off-by-One Out-of-Bounds Heap Write in fgetl()

    hashcat's fgetl() function in src/filehandling.c writes a null terminator one byte past the caller's buffer when an input line is exactly the buffer length. Attackers can trigger this out-of-bounds heap write by providing a hash file, potfile, or wordlist con…

  • Medium 5.4

    FreeRDP: Out-of-bounds read in glyph_cache_get via crafted glyph fragments

    FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, the glyph_cache_get function in libfreerdp/cache/glyph.c checks whether index is greater than cache->number instead of greater than or equal to it. A malicious RDP server can us…

  • Medium 5.5

    Microsoft Office Word Information Disclosure Vulnerability

    Off-by-one error in Microsoft Office Word allows an unauthorized attacker to disclose information locally.

  • Medium 5.3

    Off-by-One Error in GNU Emacs for Android

    GNU Emacs for Android contains an off-by-one error in the gvar table parser in src/sfnt.c. The shared-coordinate index boundary check in sfnt_vary_simple_glyph() and sfnt_vary_compound_glyph() uses a strict greater-than comparison instead of greater-than-or-e…

  • Medium 6.5

    Windows Remote Desktop Protocol (RDP) Information Disclosure Vulnerability

    Off-by-one error in Windows Remote Desktop Protocol allows an unauthorized attacker to disclose information over a network.

  • Medium 6.5

    In hostapd before 2.12, a missing bounds check in AP-mode Wi-Fi 7 (IEEE 802.11be) Multi-Link Operation (MLO) associatio…

  • Medium 6.5

    RTKLIB 2.4.3 - Off-by-One Out-of-Bounds Read in decode_ssr3 via RTCM3 SSR Message

    RTKLIB through 2.4.3 contains an off-by-one out-of-bounds read vulnerability in the decode_ssr3 function at src/rtcm3.c:1446 that allows remote attackers to trigger a global buffer overflow via crafted RTCM3 SSR messages with attacker-controlled signal mode f…

  • Medium 5.5

    Gogs: Privilege Escalation via Collaboration Access Mode Validation

    Gogs is an open source self-hosted Git service. Prior to 0.14.3, a repository admin collaborator can escalate their privileges to owner-level access by exploiting an off-by-one error in the ChangeCollaborationAccessMode function. This vulnerability is fixed i…

  • Medium 5.4

    Heap buffer overflow in Calc formula compilation

    LibreOffice Calc compiles cell formulas when opening a spreadsheet. A heap buffer overflow existed when compiling a very long formula made up of many opening tokens. The array that tracks nesting depth was allocated one element too small for that worst case, …

  • Medium 4.0

    ImageMagick: Heap Buffer Over-Write of a single byte in the JP2 encoder

    ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to versions 6.9.13-48 and 7.1.2-23, an incorrect check in the JP2 will result in an heap buffer over-write of a single byte when specifying certain options. T…

  • Medium 5.3

    ImageMagick: Out-of-Bounds Read of a single byte in meta encoder

    ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to versions 6.9.13-47 and 7.1.2-22, an off by one in the meta encoder could result in an out of bounds read of a single byte in the meta encoder. This issue h…

  • Medium 5.3

    Gnutls: gnutls: memory corruption due to off-by-one error in pkcs#12 bag handling

    A flaw was found in gnutls. An off-by-one error exists in the PKCS#12 bag element bounds check. This vulnerability allows an remote attacker to write past the internal array of a PKCS#12 bag when appending to a bag that already contains 32 elements. This memo…

  • Medium 6.2

    ImageMagick: Heap Buffer Over-Write in json and yaml encoder of a single byte due to incorrect fix

    An incorrect fix that was applied in GHSA-5592-p365-24xh could result in a heap buffer over-write of a single byte.