CVE-2026-109449
waiting for further signalsZero needs more public information before it can validate it.GHSA-7rpj-w9pf-39rr ↗EUVD-2026-102134 ↗
no check availablenot proven exploitable
cve.orgpublic pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).kevAttacks confirmed in the real world.
composer:symfony/expression-language <5.4.54; >=6; <6.4.48; >=7; <7.4.21; >=8; <8.1.9
fixed in 5.4.54, 6.4.48, 7.4.21, 8.1.9
CWE-674 Uncontrolled Recursion
ETK-2026-1665Zero's internal tracking ID, independent of the CVE number., permanent identifier
pkg:composer/symfony/expression-language
pkg:composer/symfony/symfony
5d 14h 01msince last run
13mAI analysisAnalysis: how long the AI spent reversing this signal.
description
Affected symfony/expression-language releases can crash the PHP process when parsing expressions with excessive nesting. An attacker needs access to an application feature that parses or syntax-validates untrusted expressions, including ExpressionSyntax-based validation.
mitigation
Upgrade symfony/expression-language or symfony/symfony to 5.4.54, 6.4.48, 7.4.21, or 8.1.9, as applicable. Until upgraded, prevent untrusted users from submitting expressions for parsing or validation.
fixed in 5.4.54, 6.4.48, 7.4.21, 8.1.9
check
no
exploit
no
automationDeterministic: a check that runs on its own, the same request on every target. Contextual: an agentic technique that needs to be applied per target, for bugs that depend on contextual flows.
contextual
auth requiredWhether an attacker needs an account first, based on the CVSS vector's Privileges Required.
no
EPSSEstimate of the chance this CVE is exploited in the next 30 days. Refreshed daily.
0.52%43rd percentile
agent run time
13m
cve.org record, t = 0The moment cve.org publishes the CVE in full.
2026-10-15 15:19Z
Δ to public pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).
–
Δ to kevAttacks confirmed in the real world.
–
outcome
Contextual: an exploit technique exists, but no deterministic check could cover this one.
source signals
Public signals that triggered or updated the pipeline. These are inputs for the deltas above.
- 2026-10-15 06:58Zghsa: trigger signal, started the run
- 2026-10-15 15:19Zcve.org record for CVE-2026-109449
this entry in the feed
GET /api/v1/feed/CVE-2026-109449
{ "etk_id": "ETK-2026-1665", "cve_id": "CVE-2026-109449", "display_id": "CVE-2026-109449", "ghsa_id": "GHSA-7rpj-w9pf-39rr", "euvd_id": "EUVD-2026-102134", "status": "published", "anchor_state": "anchored", "title": "Unbounded parser depth in symfony/expression-language", "summary": "Affected symfony/expression-language releases can crash the PHP process when parsing expressions with excessive nesting. An attacker needs access to an application feature that parses or syntax-validates untrusted expressions, including ExpressionSyntax-based validation.", "mitigation": "Upgrade symfony/expression-language or symfony/symfony to 5.4.54, 6.4.48, 7.4.21, or 8.1.9, as applicable. Until upgraded, prevent untrusted users from submitting expressions for parsing or validation.", "vendor": "composer", "product": "composer:symfony/expression-language", "affected": [ { "affected_notes": [], "affected_ranges": [ "<5.4.54" ], "ecosystem": "composer", "fixed_versions": [ "5.4.54" ], "package_name": "symfony/expression-language", "purl": "pkg:composer/symfony/expression-language" }, { "affected_notes": [], "affected_ranges": [ ">=6", "<6.4.48" ], "ecosystem": "composer", "fixed_versions": [ "6.4.48" ], "package_name": "symfony/expression-language", "purl": "pkg:composer/symfony/expression-language" }, { "affected_notes": [], "affected_ranges": [ ">=7", "<7.4.21" ], "ecosystem": "composer", "fixed_versions": [ "7.4.21" ], "package_name": "symfony/expression-language", "purl": "pkg:composer/symfony/expression-language" }, { "affected_notes": [], "affected_ranges": [ ">=8", "<8.1.9" ], "ecosystem": "composer", "fixed_versions": [ "8.1.9" ], "package_name": "symfony/expression-language", "purl": "pkg:composer/symfony/expression-language" }, { "affected_notes": [], "affected_ranges": [ "<5.4.54" ], "ecosystem": "composer", "fixed_versions": [ "5.4.54" ], "package_name": "symfony/symfony", "purl": "pkg:composer/symfony/symfony" }, { "affected_notes": [], "affected_ranges": [ ">=6", "<6.4.48" ], "ecosystem": "composer", "fixed_versions": [ "6.4.48" ], "package_name": "symfony/symfony", "purl": "pkg:composer/symfony/symfony" }, { "affected_notes": [], "affected_ranges": [ ">=7", "<7.4.21" ], "ecosystem": "composer", "fixed_versions": [ "7.4.21" ], "package_name": "symfony/symfony", "purl": "pkg:composer/symfony/symfony" }, { "affected_notes": [], "affected_ranges": [ ">=8", "<8.1.9" ], "ecosystem": "composer", "fixed_versions": [ "8.1.9" ], "package_name": "symfony/symfony", "purl": "pkg:composer/symfony/symfony" } ], "cwes": [ 674 ], "cvss_score": 8.7, "cvss_src": "cna_vendor", "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", "epss_score": 0.0052, "epss_percentile": 0.4328, "epss_asof": "2026-10-20", "automation": "contextual", "check": false, "check_confidence_basis": null, "exploit": false, "pipeline_minutes": 12.710180116666667, "t0_at": "2026-10-15T15:19:08.663000+00:00", "signals": { "trigger_signal": { "at": "2026-10-15T06:58:42+00:00", "days": -0.34753082175925926, "is_lower_bound": false, "measured_at": "2026-10-15T15:19:08.663000+00:00", "url": "https://github.com/symfony/symfony/security/advisories/GHSA-7rpj-w9pf-39rr" } } }
published 2026-10-15 09:59Z
last change 2026-10-21 05:31Z
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