Answer in brief
CVE-2026-108082 records a High severity (CVSS 8.7) vulnerability in Symfony: ReDoS in HeaderUtils::split() Reachable Through the Cache-Control Request Header. The current sources do not mark it as known exploited. The current feed maps sensiolabs/symfony/http-foundation (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps sensiolabs/symfony/http-foundation (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| sensiolabs/symfony/http-foundationgeneric | >=v4.1.0-BETA1 <v5.4.54 || >=v6.0.0-BETA1 <v6.4.46 || >=v7.0.0-BETA1 <v7.4.19 || >=v8.0.0-BETA1 <v8.1.7 | v5.4.54, v6.4.46, v7.4.19, v8.1.7 |
Published upstream
Oct 15, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 15, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 15, 2026
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to versions 5.4.54, 6.4.46, 7.4.19, and 8.1.7, HeaderUtils::split() parsed header values with a pattern whose token alternative also matched whitespace, followed by a (?<!\s) lookbehind. A run of whitespace placed before a separator could be divided among the iterations of the enclosing repetition in exponentially many ways, and the engine tried all of them before settling. HeaderBag calls it for the Cache-Control header whenever a Request is built, so any application handling HTTP requests is reachable, with no authentication. A single request carrying such a header costs close to a second of CPU (813 ms for a run of 17 spaces in an 8 KB header on PHP 8.5, doubling with each extra space). From 18 spaces on, preg_match_all() gives up at pcre.backtrack_limit and split() returns an empty array, so every directive of the header is silently dropped. This issue affects symfony/http-foundation v4.1.0-BETA1 through v5.4.53, v6.0.0-BETA1 through v6.4.45, v7.0.0-BETA1 through v7.4.18, and v8.0.0-BETA1 through v8.1.6.
Quoted source text, attributed separately from HOL analysis.