CVE-2026-74765 Affecting perl-Net-IDN-Encode-debugsource package, versions <0:2.590-1.amzn2023.0.1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-AMZN2023-PERLNETIDNENCODEDEBUGSOURCE-20856695
- published13 Oct 2026
- disclosed22 Sept 2026
Introduced: 22 Sep 2026
NewCVE-2026-74765 (opens in a new tab)How to fix?
Upgrade Amazon-Linux:2023 perl-Net-IDN-Encode-debugsource to version 0:2.590-1.amzn2023.0.1 or higher.
This issue was patched in ALAS2023-2026-3190.
NVD Description
Note: Versions mentioned in the description apply only to the upstream perl-Net-IDN-Encode-debugsource package and not the perl-Net-IDN-Encode-debugsource package as distributed by Amazon-Linux.
See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.
Net::IDN::Punycode versions before 2.590 for Perl allow an out-of-bounds read via integer overflow of the delta accumulator in encode_punycode.
The XS backend keeps the punycode delta, and the digit index derived from it, in a signed int. The accumulation delta += (m-n) * (h+1) has no overflow check, so a large enough code point wraps the delta and the digit index leaves the range of the 36-entry digit table. The bound before the final table access tests only for an index above 36, so a negative index passes it, as does 36 itself. Perl strings hold code points beyond the Unicode range, and one such code point overflows the accumulation on its own. Valid input wraps it as well, for example 1927 ASCII letters followed by U+10FFFF. The conversion functions encode a label before they check its length, so a long label reaches the encoder through the documented API.
Only the XS backend is affected.
Encoding an attacker-supplied string copies a byte from outside the digit table into the encoded result or crashes the process.
References
- http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-74765
- https://datatracker.ietf.org/doc/html/rfc3492#section-6.4
- https://github.com/robrwo/Net-IDN-Encode/commit/27a91ccdb6c9b41f75ba198f5ae154d14e225de2.patch
- https://github.com/robrwo/Net-IDN-Encode/commit/81c7f99fe7430bdc5116081508dffdb56f376861.patch
- https://github.com/robrwo/Net-IDN-Encode/commit/89d5aa8d3504c5e96061ab76d1541a89c16157cf.patch
- https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/changes
- http://www.openwall.com/lists/oss-security/2026/09/22/11