← All CVEs

CVE-2026-66256

HIGH 7.2

Published 2026-08-13 · Last modified 2026-08-13

** UNSUPPORTED WHEN ASSIGNED ** Deserialization of Untrusted Data vulnerability in Apache Shindig. This issue affects Apache Shindig: all versions. Users with access to the Shindig REST API can send specially-crafted requests to trigger arbitrary code execution on the server. As this project is retired, we do not plan to release a version that fixes this issue. Users are recommended to find an alternative or restrict access to the instance to trusted users. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.

ELEVATED IMPACT

Severe if exploited (CVSS 7.2), but no known exploitation and low modeled probability. Patch on a normal cadence.

Exploitation likelihood

0.5%chance of exploitation in 30 days · 42nd percentile

○ In CISA KEV ○ Public exploit / PoC

Impact if exploited

7.2CVSS 3.1 · HIGH

  • ConfidentialityHigh
  • IntegrityHigh
  • AvailabilityHigh

What an attacker needs

  • Access: Reachable over the network — no local access needed
  • Privileges: Requires an admin / high-privilege account
  • User interaction: No user interaction needed
  • Complexity: No special conditions — reliably repeatable

✓ lowers the bar for an attacker · ⚠ raises it

Proof of concept & exploit code

Test against your own equipment

curl -s https://vulnpedia.com/cve/CVE-2026-66256/poc.jsonMachine-readable PoC index for this CVE (for automation).

Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-66256/poc.json

Affected

Vendors Apache Software Foundation

Products Apache Shindig Common Apache Shindig Social Api

Weakness (CWE)

  • CWE-502: Deserialization of Untrusted Data

CVSS vector

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

All CVSS metrics

  • HIGH 7.2 v3.1 · ADP Primary
    CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
  • HIGH 7.2 v3.1 · NVD Secondary
    CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Sources: NVD · CVE.org · EPSS