CVE-2026-62383: nltk versions before 3.10.2 contain a symlink-based arbitrary file read vulnerability in IPIPANCorpusReader me

Routine

MEDIUM 5.5UPGRADE

CVE-2026-62383 is a medium-severity flaw (CVSS 5.5) affecting nltk. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

nltk versions before 3.10.2 contain a symlink-based arbitrary file read vulnerability in IPIPANCorpusReader methods that bypass nltk.pathsec validation entirely. Attackers can place a symlink in the corpus root directory and read arbitrary files accessible to the process by calling channels(), domains(), categories(), or fileids() methods with the symlink filename.

Why this priority

Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	5.5 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.2% (top 92%)
CISA exploited list	No
Weakness	CWE-22
Published	2026-08-22
Last modified	2026-10-14

Publisher (CNA): VulnCheck · Vendor: nltk

Last updated 2026-10-14 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-08-22 15:16 UTCPublished CVE record published
2026-10-14 13:10 UTCUpdated Record last modified

nltk nltk UPGRADE

Affected: >= 3.10.0 and < 3.10.2

Fixed in: 3.10.2

Safe to downgrade to: a release before 3.10.0

1. Check installed version

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

2. UPGRADE to 3.10.2 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade nltk

Note

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

3. If no update is available yet, DOWNGRADE to a release before 3.10.0 (Debian / Ubuntu)

apt-cache madison nltk sudo apt install nltk=<VERSION_BEFORE_3.10.0> sudo apt-mark hold nltk

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list nltk sudo dnf downgrade nltk-<VERSION_BEFORE_3.10.0> sudo dnf versionlock add nltk

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-2026-62383?

nltk: upgrade to 3.10.2. Exact commands for each OS are on this page.

Is CVE-2026-62383 being exploited?

CVE-2026-62383 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-2026-62383 affect?

CVE-2026-62383 affects nltk. Severity is medium (CVSS 5.5). nltk versions before 3.10.2 contain a symlink-based arbitrary file read vulnerability in IPIPANCorpusReader methods that bypass nltk.pathsec validation entirely. Attackers can place a symlink in the corpus root directory and read arbitrary

How urgent is CVE-2026-62383?

Priority 26/100. Public exploit reference

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References

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