Description
FCGI versions 0.44 through 0.82, for Perl, include a vulnerable version of the FastCGI fcgi2 (aka fcgi) library.
The included FastCGI library is affected by CVE-2025-23016, causing an integer overflow (and resultant heap-based buffer overflow) via crafted nameLen or valueLen values in data to the IPC socket. This occurs in ReadParams in fcgiapp.c.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| ETHER | FCGI | 0.44 – ≤ 0.82 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libfcgi-perl | 0.79+ds-2 | — |
| Debian 13 | libfcgi-perl | 0.79+ds-2 | — |
| Debian 12 | libfcgi-perl | 0.79+ds-2 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | libfcgi-perl | 0.79-1ubuntu0.1 | USN-7527-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | libfcgi-perl | 0.78-2ubuntu0.1~esm1 | USN-7527-1 |
| Ubuntu Pro 16.04 LTS | libfcgi-perl | 0.77-1ubuntu0.1~esm1 | USN-7527-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | perl-FCGI | 1:0.82-13.1.el10_0 | RHSA-2025:8636 |
| RHEL 9 | perl-FCGI | 1:0.79-8.1.el9_6 | RHSA-2025:8635 |
| RHEL 8 | perl-FCGI | 1:0.78-12.module+el8.10.0+23147+df114ff4 | RHSA-2025:8696 |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.4 EUS | perl-FCGI | 1:0.79-8.el9_4.1 | RHSA-2025:8677 |
| RHEL 9.2 E4S | perl-FCGI | 1:0.79-8.el9_2.1 | RHSA-2025:8697 |
| RHEL 9.0 E4S | perl-FCGI | 1:0.79-8.el9_0.1 | RHSA-2025:8678 |
| RHEL 8.8 TUS | perl-FCGI | 1:0.78-11.module+el8.8.0+23188+f6366248.1 | RHSA-2025:8698 |
| RHEL 8.8 E4S | perl-FCGI | 1:0.78-11.module+el8.8.0+23188+f6366248.1 | RHSA-2025:8698 |
| RHEL 8.6 TUS | perl-FCGI | 1:0.78-11.module+el8.6.0+23193+c3786137.1 | RHSA-2025:8890 |
| RHEL 8.6 E4S | perl-FCGI | 1:0.78-11.module+el8.6.0+23193+c3786137.1 | RHSA-2025:8890 |
| RHEL 8.6 AUS | perl-FCGI | 1:0.78-11.module+el8.6.0+23193+c3786137.1 | RHSA-2025:8890 |
| RHEL 8.4 AUS | perl-FCGI | 1:0.78-11.module+el8.4.0+23229+35c4aba7.1 | RHSA-2025:8703 |
| RHEL 8.2 AUS | perl-FCGI | 1:0.78-11.module+el8.2.0+23234+edafdda3.1 | RHSA-2025:8829 |
| RHEL 7 ELS | perl-FCGI | 1:0.74-8.el7_9.1 | RHSA-2025:8625 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | perl-FCGI | 1:0.82-13.1.el10_0 | ALSA-2025:8636 |
| AlmaLinux 9 | perl-FCGI | 1:0.79-8.1.el9_6 | ALSA-2025:8635 |
| AlmaLinux 8 | perl-FCGI | 1:0.78-12.module_el8.10.0+4011+62915be2 | ALSA-2025:8696 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | perl-FCGI | 1:0.82-13.1.el10_0 | RLSA-2025:8636 |
| Rocky Linux 9 | perl-FCGI | 1:0.79-8.1.el9_6 | RLSA-2025:8635 |
| Rocky Linux 8 | perl-FCGI | 1:0.78-12.module+el8.10.0+1990+d30a9ea8 | RLSA-2025:8696 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | perl-FCGI | 1:0.74-8.amzn2.0.3 | ALAS2-2025-2880 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | perl-FCGI | No fix yet | — |
| Azure Linux 2 (CBL-Mariner) | perl-FCGI | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | perl-FCGI | 1:0.82-13.1.el10_0 | ELSA-2025-8636 |
| Oracle Linux 9 | perl-FCGI | 1:0.79-8.1.el9_6 | ELSA-2025-8635 |
| Oracle Linux 8 | perl-FCGI | 1:0.78-12.module+el8.10.0+90610+44f1ea29 | ELSA-2025-8696 |
| Oracle Linux 7 | perl-FCGI | 1:0.74-8.0.1.el7 | ELSA-2025-8625 |
Advisories 24
- ALSA-2025:8636 Important: perl-FCGI security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2025:8635 Important: perl-FCGI security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2025:8696 Important: perl-FCGI:0.78 security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2025:8890 Red Hat Security Advisory: perl-FCGI:0.78 security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8829 Red Hat Security Advisory: perl-FCGI security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8703 Red Hat Security Advisory: perl-FCGI:0.78 security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8697 Red Hat Security Advisory: perl-FCGI security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8698 Red Hat Security Advisory: perl-FCGI:0.78 security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8696 Red Hat Security Advisory: perl-FCGI:0.78 security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8678 Red Hat Security Advisory: perl-FCGI security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8677 Red Hat Security Advisory: perl-FCGI security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8636 Red Hat Security Advisory: perl-FCGI security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8635 Red Hat Security Advisory: perl-FCGI security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2025:8625 Red Hat Security Advisory: perl-FCGI security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- USN-7527-1 libfcgi-perl vulnerability Ubuntu Security Notices (USN) · Jun 25, 2026
- WID-SEC-2025-1273 Perl: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 26, 2025
- RLSA-2025:8636 Important: perl-FCGI security update Rocky Linux Security Advisories · Oct 8, 2025
- RLSA-2025:8635 Important: perl-FCGI security update Rocky Linux Security Advisories · Oct 7, 2025
- RLSA-2025:8696 Important: perl-FCGI:0.78 security update Rocky Linux Security Advisories · Jul 29, 2025
- ELSA-2025-8636 Important: perl-FCGI security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Jun 30, 2025
- ELSA-2025-8625 Important: perl-FCGI security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jun 23, 2025
- ELSA-2025-8696 Important: perl-FCGI:0.78 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jun 18, 2025
- ALAS2-2025-2880 Moderate: perl-FCGI security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jun 12, 2025
- ELSA-2025-8635 Important: perl-FCGI security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jun 9, 2025
References
- http://www.openwall.com/lists/oss-security/2025/04/23/4 mailing-list
- https://github.com/FastCGI-Archives/fcgi2/issues/67 issue-tracking
- https://github.com/FastCGI-Archives/fcgi2/releases/tag/2.4.5 patch
- https://www.synacktiv.com/en/publications/cve-2025-23016-exploiting-the-fastcgi-library technical-description
- https://github.com/perl-catalyst/FCGI/issues/14 issue-tracking
- https://patch-diff.githubusercontent.com/raw/FastCGI-Archives/fcgi2/pull/74.patch patch