CVE-2026-80490 Details
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.
A vulnerability exists in Algorithm::AhoCorasick::XS for Perl, affecting versions through 0.04. The issue arises because the library reads the length of the haystack string before the scalar is properly stringified. This flaw is present in the matches, first_match, and match_details methods, which rely on the T_STD_STRING typemap to convert Perl scalars into strings. The SvCUR macro, used to determine the length of the scalar, can return an invalid length if the input is a reference, integer, or float, leading to an out-of-bounds read that can crash the process. This vulnerability can be triggered when the haystack is a numeric value, a result of decoded JSON, or a numeric database column, and also when using a blessed object as a haystack.
Users can apply the patch available in the linked pull request on GitHub. For those unable to apply the patch, ensure that all input passed to the matching functions is stringified.
Metrics
CVSS 4.0 Severity and Vector Strings:
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Sep 30, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/richardjharris/Algorithm-AhoCorasick-XS/pull/1 | CPANSec | Issue TrackingVendor |
| https://metacpan.org/release/RJH/Algorithm-AhoCorasick-XS-0.04/source/typemap#L14 | CPANSec | Source CodeVendor |
| https://rt.cpan.org/Ticket/Display.html?id=181560 | CPANSec | Issue TrackingMailing ListVendor |
| https://security.metacpan.org/patches/A/Algorithm-AhoCorasick-XS/0.04/CVE-2026-80490-r1.patch | CPANSec | Broken LinkSource CodeVendor |
| http://www.openwall.com/lists/oss-security/2026/09/30/15 | CVE | AdvisoryMailing ListRemedy |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-125 | Out-of-bounds Read | CPANSec |
Affected Products
| Product | Versions |
|---|---|
| Algorithm::AhoCorasick::XS | <= 0.04 |
CPE
Remediation
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Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Sep 30, 2026 | CVE Modified | CVE |
| Sep 30, 2026 | New CVE Received | CPANSec |
Volerion