How severe is CVE-2026-46637?

CVE-2026-46637 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-46637 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-46637?

CVE-2026-46637 affects Symfony Twig. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-46637?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-46637 published?

CVE-2026-46637 was published on 2026-07-14 and last updated on 2026-07-16.

CVE-2026-46637

CVE-2026-46637 is a medium-severity vulnerability in Symfony Twig with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v4: 5.1
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Symfony Twig
Published: 2026-07-14
Last modified: 2026-07-16

Description

Twig is a template language for PHP. Prior to 3.26.0, several filters in twig/markdown-extra and twig/cssinliner-extra are registered with is_safe => [all], causing Twig to treat plain text or HTML output as safe in HTML, JavaScript, CSS, URL, and other contexts where the output is not properly escaped. This issue is fixed in version 3.26.0.

Frequently asked questions

What is CVE-2026-46637?: Twig is a template language for PHP. Prior to 3.26.0, several filters in twig/markdown-extra and twig/cssinliner-extra are registered with is_safe => [all], causing Twig to treat plain text or HTML output as safe in HTML, JavaScript, CSS, URL, and other contexts where the output is not properly escaped. This issue is fixed in version 3.26.0.
How severe is CVE-2026-46637?: CVE-2026-46637 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-46637 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-46637?: CVE-2026-46637 affects Symfony Twig. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-46637?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-46637 published?: CVE-2026-46637 was published on 2026-07-14 and last updated on 2026-07-16.

References

Affected products (1)

cpe:2.3:a:symfony:twig:*:*:*:*:*:*:*:*

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