Cyber Resilience

CVE-2026-48808

Access Control in Symfony Twig ≤ 3.27.0

Published
14 July 2026
Modified
17 July 2026
Patch / advisory
CVSS Score v4 6.0
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/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
EPSS Score 0.0024 15th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-48808 is a medium-severity Protection Mechanism Failure (CWE-693) vulnerability in Symfony Twig. Its CVSS base score is 6.0 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 15th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Twig is a template language for PHP. Prior to 3.27.0, the column filter passes the active sandbox state as a boolean but does not forward the current Source to SandboxExtension::checkPropertyAllowed(), so SourcePolicyInterface decisions are lost and a template author can…

more

read public or magic properties not allowed by the sandbox policy. This issue is fixed in version 3.27.0.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

Sandbox bypass in Twig (PHP templating) directly enables exploitation of public-facing web applications to access unauthorized properties/data.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-48806Same product: Symfony Twig
CVE-2026-49981Same product: Symfony Twig
CVE-2026-48807Same product: Symfony Twig
CVE-2026-46639Same product: Symfony Twig
CVE-2026-46638Same product: Symfony Twig
CVE-2026-47732Same product: Symfony Twig
CVE-2026-46634Same product: Symfony Twig
CVE-2026-46635Same product: Symfony Twig
CVE-2026-24425Same product: Symfony Twig
CVE-2026-46628Same product: Symfony Twig

Affected Assets

symfony
twig
≤ 3.27.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 13 hardening rules · 8 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.3.3
  • V6.6.3
  • V10.2.2

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces the sandbox policy on property access so that SourcePolicyInterface decisions cannot be bypassed by the column filter.

prevent

Ensures templates execute with only the minimal property access permitted by the active sandbox policy, blocking the unauthorized reads described in the CVE.

SC-18 Mobile Code partial match
prevent

Restricts execution of untrusted template code (mobile code) and requires sandbox controls that would have prevented the column-filter bypass.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-03 mostly match
prevents

Enforcing authentication directly implements a core protection mechanism whose absence or misuse is the CWE.

PR.AA-05 mostly match
prevents

Defining and enforcing access authorizations is a protection mechanism; proper use prevents the CWE.

PR.DS-01 mostly match
prevents

Cryptographic and integrity controls are protection mechanisms whose correct deployment mitigates the CWE.

PR.DS-02 mostly match
prevents

Encryption and integrity protections for transit are explicit protection mechanisms.

PR.IR-01 mostly match
prevents

Logical network protections are protection mechanisms whose failure matches the CWE.

PR.PS-01 partial match
prevents

Hardened configuration baselines ensure protection mechanisms are correctly applied and maintained.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring consistency between access rights and classification plus formal approval steps ensures that the authorization logic correctly distinguishes between entities that should and should not be granted access.

prevents

Enforcing policy-driven approval and role-change reviews stops incorrect or stale authorization decisions from remaining in effect after job changes or terminations.

detects

Systematic verification that security mechanisms operate according to defined standards reduces the likelihood that protection mechanisms are bypassed or disabled.

mitigates

Hardening devices, disabling vulnerable protocols, and maintaining accurate network diagrams reduce the likelihood that a protection mechanism is misconfigured or left in a weak state.

prevents

By tying access rights to identity, device, location and classification, the control reduces the likelihood that an authorization decision will be based on an incorrect or bypassed policy.

none

Requiring defined escalation paths, crisis activation criteria, and coordination procedures strengthens the overall protection mechanism so that a single control failure is less likely to leave the organization exposed.

References