Handler on Duty: Johannes Ullrich
Threat Level: green
| Published | 2026-10-23 21:17:21 |
|---|---|
| Last Modified | 2026-10-23 21:17:21 |
| AKA | CVE-2026-113877 |
| Summary | HTTP::Headers::ActionPack versions before 0.10 for Perl allow CPU exhaustion via Accept-Language ranges matched as regular expressions. _language_match interpolates each Accept-Language range into the pattern `/^$range\-/i` without escaping it, so regular expression syntax in the header reaches the regex engine. A 12-byte range such as `(a?|b?){26}z` backtracks for seconds, and each increment of the quantifier doubles the time. An invalid range such as `(` fails to compile. A remote attacker can exhaust CPU, or make choose_language die, in any application that passes an untrusted Accept-Language header to it. |
| Access Vector | Local | Adjacent | Network |
|---|---|---|---|
| Access Complexity | Low | Medium | High |
| Authentication | None | Single | Multiple |
| Confidentiality | None | Partial | Complete |
| Integrity | None | Partial | Complete |
| Availability | None | Partial | Complete |
