CVE-2026-80490Algorithm::AhoCorasick::XS versions through 0.04 for Perl read the haystack string length before the scalar is stringified
- 4.4MediumCVSS base score
- 0.12%Exploitation in 30 daysEPSS · top 98% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Algorithm::AhoCorasick::XS versions through 0.04 for Perl read the haystack string length before the scalar is stringified. The matches, first_match and match_details methods use the T_STD_STRING typemap to translate Perl scalars (SVs) into strings via the std::string constructor, using the SvPV macro to stringify the haystack input, and the SvCUR macro to determine the length of the SV. When the input SVs are references, integers (IVs) or floats (NVs), the SvCUR macro will return an invalid length if it is run before the input is stringified, leading to an out-of-bounds read which can abort the process. Note that the evaluation order of arguments to std::string is unspecified. Depending on the compiler, SvCUR may be run first and lead to an abort that cannot be caught within Perl. This can be triggered when the haystack is a numeric value, for example, my $ac = Algorithm::AhoCorasick::XS->new( [ "11", "22" ] ); $ac->matches( 211 ); This can occur when the haystack is the result of reading data from decoded JSON or a numeric database column. It can also be triggered when using a blessed object as a haystack.
Timeline
ID reserved
By CPANSec
- 35 days later
· 35 days later
Published
- 40 days later
· 40 days later
First scored
Medium 4.4
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium4.4 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L |
| NVDNVD · Deferred | 3.1 | Medium4.4 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L |
- EPSS (exploitation in 30 days)
- 0.12% · top 98% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.4.
Affected products
Algorithm-AhoCorasick-XS
- affected ≤ 0.04
What to do
Workaround: No fixed release is available. Apply the patch or the change in the linked pull request. For deployments that cannot apply the patch, ensure that all input passed to the matching functions is stringified, for example $ac->matches( "$input" );
References
References5
- https://rt.cpan.org/Ticket/Display.html?id=181560 (opens in a new tab)vendor-advisoryissue-tracking
- https://metacpan.org/release/RJH/Algorithm-AhoCorasick-XS-0.04/source/typemap#L14 (opens in a new tab)
- https://github.com/richardjharris/Algorithm-AhoCorasick-XS/pull/1 (opens in a new tab)issue-tracking
- https://security.metacpan.org/patches/A/Algorithm-AhoCorasick-XS/0.04/CVE-2026-80490-r1.patch (opens in a new tab)patch
- http://www.openwall.com/lists/oss-security/2026/09/30/15 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-90025 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-80490)Record last updated .