# CVE-2026-58186: Apache Traffic Server unsafe decoding in webp_transform plugin

Source: https://junglewise.ai/threats/cve-2026-58186-apache-traffic-server-unsafe-decoding-in-webp-transform-plugin  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-29. Updated: 2026-07-29  
License: CC BY 4.0 with a link back

CVE-2026-58186 · Severity: high · CVSS 7.5 · Published 2026-07-29

Apache Traffic Server, a high-performance caching proxy used to speed up web content delivery, contains a vulnerability in its image transformation plugin. An attacker could exploit this to cause the system to process images unsafely and serve incorrect, cached data. This primarily impacts the availability and reliability of the web services being accelerated by the proxy.

Technologies: [Apache Traffic Server](https://junglewise.ai/threats/technologies/traffic-server). Vendors: [Apache](https://junglewise.ai/threats/vendors/apache).

## Quick answers

**Is CVE-2026-58186 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-58186 being exploited in the wild.

**How severe is CVE-2026-58186?** High severity, with a CVSS score of 7.5, published 29 July 2026.

**Which products and versions are affected?** Apache Traffic Server 8.0.0 through 8.1.9, 9.0.0 through 9.2.14, 10.0.0 through 10.1.3.

**Is there a fix for CVE-2026-58186?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-58186 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-58186?** Check whether you run Apache Traffic Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A vulnerability exists in the webp_transform plugin of Apache Traffic Server due to improper input validation (CWE-20) during image decoding. The plugin may decode data unsafely and subsequently serve mislabeled responses that are stored in the cache. This is a network-reachable vulnerability that requires no authentication or user interaction. The primary impact is on service availability (Denial of Service), as indicated by the CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H vector. Users are advised to upgrade to versions 9.2.15 or 10.1.4 to resolve the issue.

## Affected products

- Apache Traffic Server 8.0.0 through 8.1.9, 9.0.0 through 9.2.14, 10.0.0 through 10.1.3

## Timeline

- 2026-07-29: disclosed
- 2026-07-29: advisory

## References

- [https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6d](https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6d)

## Related threats

- [Apache Traffic Server null pointer dereference in request tear-down](https://junglewise.ai/threats/cve-2026-112381-apache-traffic-server-can-crash-with-a-null-pointer-dereference)
- [Apache Traffic Server connection stall with chunked transfer trailers dropped](https://junglewise.ai/threats/cve-2026-111817-apache-traffic-server-can-stall-a-chunked-transfer-that-it)
- [Apache Traffic Server TLS session resumption bypass of client certificate verification](https://junglewise.ai/threats/cve-2026-111815-apache-traffic-server-can-resume-a-tls-session-across-sni)
- [Apache Traffic Server TLS session reuse with mismatched client certificates](https://junglewise.ai/threats/cve-2026-111814-apache-traffic-server-s-default-outbound-session-sharing-policy)
- [Apache Traffic Server origin_server_auth AWS request signing bypass](https://junglewise.ai/threats/cve-2026-111812-apache-traffic-server-s-origin-server-auth-plugin-lets-a-client)