CVE-2026-46406: Claude Code is an agentic coding tool

Q: How do I fix CVE-2026-46406?

claude code: upgrade to 2.1.128. Exact commands for each OS are on this page.

Q: Is CVE-2026-46406 being exploited?

CVE-2026-46406 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-2026-46406 affect?

CVE-2026-46406 affects claude code. Severity is medium (CVSS 6.1). Claude Code is an agentic coding tool. From 2.1.59 until 2.1.128, the Claude Code /copy command wrote responses to a hardcoded, predictable path (/tmp/claude/response.md) without UID isolation, randomness, or symlink protection. The file w

Q: How urgent is CVE-2026-46406?

Priority 22/100. No elevated risk signals yet.

Routine

MEDIUM 6.1UPGRADE

CVE-2026-46406 is a medium-severity flaw (CVSS 6.1) affecting claude code. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Claude Code is an agentic coding tool. From 2.1.59 until 2.1.128, the Claude Code /copy command wrote responses to a hardcoded, predictable path (/tmp/claude/response.md) without UID isolation, randomness, or symlink protection. The file was created world-readable (0644) in a world-traversable directory (0755), allowing any local user to read a privileged user's Claude response, which could contain secrets or credentials. Additionally, because t

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	6.1 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	Required
EPSS exploit chance	0.2% (top 96%)
CISA exploited list	No
Weakness	CWE-59, CWE-200, CWE-377
Published	2026-06-29
Last modified	2026-10-25

Publisher (CNA): GitHub, Inc. · Vendor: anthropic

Last updated 2026-10-25 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-06-29 15:16 UTCPublished CVE record published
2026-10-25 21:10 UTCUpdated Record last modified

anthropic claude code UPGRADE

Affected: >= 2.1.58 and < 2.1.128

Fixed in: 2.1.128

Safe to downgrade to: a release before 2.1.58

1. Check installed version

npm ls claude-code

2. UPGRADE to 2.1.128

npm install claude-code@">=2.1.128"

3. If no update is available yet, DOWNGRADE to a release before 2.1.58

npm view claude-code versions npm install claude-code@"<2.1.58"

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

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-2026-46406?

claude code: upgrade to 2.1.128. Exact commands for each OS are on this page.

Is CVE-2026-46406 being exploited?

CVE-2026-46406 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-2026-46406 affect?

CVE-2026-46406 affects claude code. Severity is medium (CVSS 6.1). Claude Code is an agentic coding tool. From 2.1.59 until 2.1.128, the Claude Code /copy command wrote responses to a hardcoded, predictable path (/tmp/claude/response.md) without UID isolation, randomness, or symlink protection. The file w

How urgent is CVE-2026-46406?

Priority 22/100. No elevated risk signals yet.

Related CVEs

CVE-2026-54316 CRITICAL 9.1 UPGRADE Claude Code is an agentic coding tool
CVE-2026-55607 HIGH 8.8 UPGRADE Claude Code is an agentic coding tool

References

← Back to latest CVEs