Description
inih before r63 contains a one-byte stack buffer under-read in ini_parse_stream() in ini.c that allows attackers to read abyss[-1] via an embedded NUL byte after an overlong line. Attackers can supply an INI file or string with a line of at least INI_MAX_LINE-1 bytes followed by a NUL byte, causing undefined behavior reported by memory sanitizers.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| benhoyt | inih | < r63 | r63 |
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.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | libinih | No fix yet | — |
| Ubuntu 26.04 LTS | libinih | No fix yet | — |
| Ubuntu 24.04 LTS | libinih | No fix yet | — |
| Ubuntu 22.04 LTS | libinih | No fix yet | — |
| Ubuntu 20.04 LTS | libinih | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | libinih | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | inih | 63-1.1 | openSUSE-SU-2026:12432-1 |
Advisories 1
- openSUSE-SU-2026:12432-1 libinih-devel-63-1.1 on GA media SUSE / openSUSE Security Updates · Nov 6, 2026
References
- https://github.com/benhoyt/inih/pull/206 issue-tracking patch
- https://github.com/benhoyt/inih/issues/223 issue-tracking
- https://github.com/benhoyt/inih/commit/8e06f6b77b5d4471bdc6d85ada81b67d37354a5c patch
- https://github.com/benhoyt/inih/blob/r62/ini.c#L162-L169 technical-description
- inih r63 Release Notes release-notes
- https://hackmd.io/@haindpwn/inih-long-line-discard-oob-read technical-description
- VulnCheck Advisory: inih before r63 Stack Buffer Under-Read in ini_parse_stream Discard Loop third-party-advisory