# CVE-2026-107379: enshrined/svg-sanitize: Denial of Service via DTD Attribute Declaration Crash

> An attacker can cause a denial of service by submitting crafted SVG content that crashes the PHP worker via a double attribute removal bug.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 Oct 2026
- **Updated:** 9 Oct 2026
- **Also known as:** GHSA-v383-3rw5-q8rf

## What is CVE-2026-107379?

CVE-2026-107379 is a medium-severity denial of service vulnerability in darylldoyle svg-sanitizer, published on 8 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

savg-sanitizer is a PHP SVG/XML sanitizer. Prior to 1.0.0, svg-sanitizer allows a crafted SVG DTD with a #FIXED attribute default to make cleanAttributesOnWhitelist() perform a double DOMElement::removeAttribute() call on the same attribute name in src/Sanitizer.php. The first removal deletes the explicit attribute, while the DTD default rematerializes the value before the href safety path performs the second removal, which can corrupt libxml state and terminate the PHP worker. An attacker who can submit SVG content to a sanitization endpoint can repeatedly interrupt workers and degrade or exhaust application availability. This issue is fixed in version 1.0.0.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-107379?

2 open source packages ship an affected version, including enshrined/svg-sanitize.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `enshrined/svg-sanitize` | Packagist | All versions | 1.0.0 |
| `enshrined/svg-sanitize` | Packagist | All versions | 1.0.0 |

## How do I fix CVE-2026-107379?

Upgrade enshrined/svg-sanitize to 1.0.0 or later.

## Is CVE-2026-107379 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-107379 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-107379 and fix it if it is affected.

What it is: CVE-2026-107379 is a medium-severity denial of service vulnerability in darylldoyle svg-sanitizer, published on 8 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-107379 exists.

Affected packages and fixed versions:
- enshrined/svg-sanitize (Packagist): affected all versions; fixed in 1.0.0
- enshrined/svg-sanitize (Packagist): affected all versions; fixed in 1.0.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-107379/ (Markdown: https://insights.sbomify.com/CVE-2026-107379/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-107379
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-107379
- OSV: https://osv.dev/vulnerability/CVE-2026-107379

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-107379/
Summaries are generated and may contain mistakes; the official description above is the record.