---
title: "CVE-2026-108082: Symfony HTTP Foundation - Denial of Service"
description: "Symfony HTTP Foundation < 5.4.54, < 6.4.46, < 7.4.19, and < 8.1.7 contains a denial of service caused by exponential backtracking in HeaderUtils::split() when parsing Cache-Control headers, letting remote attackers cause high CPU usage, exploit requires sending crafted HTTP requests."
url: https://panop.io/threat-heartbeat/CVE-2026-108082/
---

# CVE-2026-108082 Symfony HTTP Foundation - Denial of Service

Symfony HTTP Foundation < 5.4.54, < 6.4.46, < 7.4.19, and < 8.1.7 contains a denial of service caused by exponential backtracking in HeaderUtils::split() when parsing Cache-Control headers, letting remote attackers cause high CPU usage, exploit requires sending crafted HTTP requests.

CVSS base score 8.7 /10

High

CISA KEV

Not listed

Public exploit

None known

Authentication

Not required

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-108082)

## Details

Type

Denial of Service

Impact

Denial Of Service

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Published

15 October 2026

Updated

15 October 2026

Weakness

[CWE-1333](https://cwe.mitre.org/data/definitions/1333.html)

## Vendor fix

Upgrade to versions 5.4.54, 6.4.46, 7.4.19, 8.1.7 or later.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-108082](https://nvd.nist.gov/vuln/detail/CVE-2026-108082)
- [https://github.com/symfony/symfony/pull/66048](https://github.com/symfony/symfony/pull/66048)
- [https://github.com/symfony/symfony/pull/66491](https://github.com/symfony/symfony/pull/66491)
- [https://github.com/symfony/symfony/security/advisories/GHSA-r925-mgvr-h9cc](https://github.com/symfony/symfony/security/advisories/GHSA-r925-mgvr-h9cc)
- [https://symfony.com/blog/cve-2026-108082-redos-in-headerutils-split-reachable-through-the-cache-control-request-header](https://symfony.com/blog/cve-2026-108082-redos-in-headerutils-split-reachable-through-the-cache-control-request-header)

[← All CVEs](https://panop.io/threat-heartbeat/)

## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

[Book a demo](https://panop.io/demo)