# CVE-2026-58186

CVE-2026-58186 is a high-severity vulnerability rated 8.2/10 on the CVSS scale. The Apache Traffic Server `webp_transform` plugin can decode unsafely and serve mislabeled, cacheable responses.

This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.

Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue. EPSS estimates a 0.37% chance of exploitation in the next 30 days.

## Description

The Apache Traffic Server `webp_transform` plugin can decode unsafely and serve mislabeled, cacheable responses.

This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.

Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.

## Metrics

CVSS 3.1 7.5/10  
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS 4.0 8.2/10  
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/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 Probability 0.37%

30.1th percentile

Probability of exploitation in the next 30 days. [Learn more](https://www.first.org/epss/)

## Weakness Enumeration

- [CWE-20](https://cwe.mitre.org/data/definitions/20.html)

## Affected Software

| Vendor | Product | Versions |
| --- | --- | --- |
| Apache | Traffic Server | >= 8.0.0, <= 8.1.9 |
| Apache | Traffic Server | >= 9.0.0, < 9.2.15 |
| Apache | Traffic Server | >= 10.0.0, < 10.1.4 |

## References

- [Mailing List, Vendor Advisory](https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6d)

## Timeline

Published Jul 29, 2026

Last Modified Jul 31, 2026

Status Analyzed

## Frequently Asked Questions

**What is CVE-2026-58186?**  
The Apache Traffic Server `webp_transform` plugin can decode unsafely and serve mislabeled, cacheable responses.

This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.

Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.

**How severe is CVE-2026-58186?**  
CVE-2026-58186 has a CVSS score of 8.2/10 (HIGH severity). The EPSS model estimates a 0.37% probability of exploitation in the next 30 days.

**How do I fix CVE-2026-58186?**  
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also [run a Strix scan](https://app.strix.ai/) to test if your systems are affected.