CVE-2026-48806: symfony twig Protection Mechanism Failure
CVSS: 9.1v3.1CriticalAnalyzed
AliasesUBUNTU-CVE-2026-48806DEBIAN-CVE-2026-48806
Published 14-07-2026Last modified 15-07-2026
Vulnerability summary
CVE-2026-48806 is a critical (CVSS 9.1) Protection Mechanism Failure vulnerability in symfony twig. EPSS estimates a 0.42% chance of exploitation in the next 30 days, higher than 34.7% of scored vulnerabilities.
CVSS score
9.1/10
010
Critical · v3.1 (NVD)EPSS score
0.42%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 14-07-2026PublishedVulnerability first disclosed.
- 15-07-2026Last modifiedVulnerability information updated.
Description
Twig is a template language for PHP. Prior to 3.27.0, ArrayExpression does not guard dynamic mapping keys that are coerced to strings, allowing PHP to invoke __toString() on a Stringable object used as a mapping key without calling SandboxExtension::ensureToStringAllowed(). This issue is fixed in version 3.27.0.
CVSS metrics
6 scores · 4 sources · 2 versionsHigh 7.1Preferred score · CVE.org (CNA)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:NSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated7.1HighCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
- NVDNIST7.1HighCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/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
Critical 9.1Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- OSV · DebianEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS trend
Probability
0.42%
Chance of exploitation in the next 30 days
Percentile
35%
Versus all other CVEs
30-day change
0.00 pp
From 0.42% on 20-09-2026
20-09-202620-10-2026
EPSS score0.42%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-693Protection Mechanism FailureThe product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product.
- CWE-863Incorrect AuthorizationThe product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
Affected systems
Debian1 product
- php-twig< 3.27.0-1
Symfony1 product
- twig< 3.27.0
Twigphp1 product
- twig< 3.27.0
Ubuntu1 product
- php-twigAll versions (No fix recorded)
4 vendors · 4 products
