CVE-2015-8866

critical

Published 2016-05-22 · Modified 2026-05-06

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CVSS v3

9.6

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

CVSS v4 NEW

—

not yet in upstream

VIR risk

9.6

Description

ext/libxml/libxml.c in PHP before 5.5.22 and 5.6.x before 5.6.6, when PHP-FPM is used, does not isolate each thread from libxml_disable_entity_loader changes in other threads, which allows remote attackers to conduct XML External Entity (XXE) and XML Entity Expansion (XEE) attacks via a crafted XML document, a related issue to CVE-2015-5161.

Predictions

Exploit likelihood

96%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

SUSE Affected 3 releases

Version	Status	Fixed in
42.1	Affected	—
13.2	Affected	—
—	Affected	—

Ubuntu Affected 3 releases

Version	Status	Fixed in
15.10	Affected	—
14.04	Affected	—
12.04	Affected	—

Application impact

Vendor	Product	Versions	Fixed
php	php	`{"startIncluding":"5.5.0","endExcluding":"5.5.22"}`	`5.5.22`

References

CWEs

CWE-611

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.