CVE-2020-29511: The encoding/xml package in Go (all versions) does not correctly preserve the semantics of element namespace p

Q: How do I fix CVE-2020-29511?

go: upgrade to 1.17; trident: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2020-29511 being exploited?

CVE-2020-29511 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2020-29511 affect?

CVE-2020-29511 affects go, trident. Severity is critical (CVSS 9.8). The encoding/xml package in Go (all versions) does not correctly preserve the semantics of element namespace prefixes during tokenization round-trips, which allows an attacker to craft inputs that behave in conflicting ways during different

Q: How urgent is CVE-2020-29511?

Priority 59/100. Critical severity; Remotely exploitable, no login, no user action

This month

CRITICAL 9.8REMOTEUPGRADEMITIGATE

CVE-2020-29511 is a critical-severity flaw (CVSS 9.8) affecting go, trident. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The encoding/xml package in Go (all versions) does not correctly preserve the semantics of element namespace prefixes during tokenization round-trips, which allows an attacker to craft inputs that behave in conflicting ways during different stages of processing in affected downstream applications.

Why this priority

Critical severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	2.0% (top 20%)
CISA exploited list	No
Weakness	CWE-115
Published	2020-12-14
Last modified	2026-06-17

Publisher (CNA): Mattermost, Inc. · Vendor: golang · netapp

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2020-12-14 20:15 UTCPublished CVE record published
2026-06-17 03:11 UTCUpdated Record last modified

golang go UPGRADE

Affected: < 1.17

Fixed in: 1.17

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy go || rpm -q go || go --version

2. UPGRADE to 1.17 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade go

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade go

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

netapp trident MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy trident || rpm -q trident || trident --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2020-29511?

go: upgrade to 1.17; trident: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2020-29511 being exploited?

CVE-2020-29511 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2020-29511 affect?

CVE-2020-29511 affects go, trident. Severity is critical (CVSS 9.8). The encoding/xml package in Go (all versions) does not correctly preserve the semantics of element namespace prefixes during tokenization round-trips, which allows an attacker to craft inputs that behave in conflicting ways during different

How urgent is CVE-2020-29511?

Priority 59/100. Critical severity; Remotely exploitable, no login, no user action

Software pages

Go (Golang) vulnerabilities

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References

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