CVE-2026-56859: Go standard library encoding/xml · Unthrottled Resource Allocation
Affects Go standard library encoding/xmlSource CVE Database V5
Not known to be exploited · CVSS 7.5 High · fixed in 1.27.0-rc.3 : patch Go standard library encoding/xml soon.
Data as of 12 Nov 2026, 23:24 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 47% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.27.0-rc.3, 1.26.6, 1.25.13
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Upgrade Go standard library encoding/xml to 1.27.0-rc.3, 1.26.6 or 1.25.13.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Go standard libraryencoding/xml | Affected
| Fixed in
|
| Go standard libraryencoding/xml | Affected
| Fixed in
|
| Go standard libraryencoding/xml | Affected
| Fixed in
|
Goencoding/xmlpkg:golang/encoding/xmlOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, users should consider mitigating risk by limiting exposure to untrusted XML input or applying application-level resource constraints.
Description
Previously, DecodeElement would reset the depth counter causing it to never fire; this could lead to stack exhaustion.