How severe is CVE-2020-26213?

CVE-2020-26213 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2020-26213?

CVE-2020-26213 affects the following packages: ktbs.dev/teler (Go). Ecosystems affected: Go.

How do I fix CVE-2020-26213?

Update ktbs.dev/teler to 0.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-26213 is resolved across your whole dependency graph.

How do I detect CVE-2020-26213 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ktbs.dev/teler, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2020-26213 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2020-26213 actively exploited in the wild?

No public exploit code has been indexed for CVE-2020-26213 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2020-26213?

CVE-2020-26213 has an EPSS (Exploit Prediction Scoring System) score of 1.4%, placing it in the 72th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2020-26213?

CVE-2020-26213 is classified as NULL Pointer Dereference (CWE-476). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2020-26213 published, and has it been updated?

CVE-2020-26213 was published on November 6, 2020 and was last updated on August 27, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

HIGH severity

CVE-2020-26213 — teler

HIGHFix: kitabisa/teler@ec60820

CVE-2020-26213 is a high-severity (CVSS 7.5) NULL Pointer Dereference vulnerability in ktbs.dev/teler. A fix is available for ktbs.dev/teler — see the affected versions and patch details below.

Denial-of-Service within Docker container

Also known asGHSA-jhj6-5mh6-4pvfGO-2022-0903

Published

Nov 6, 2020

Updated

Aug 27, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 10, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

1.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs72th percentile — riskier than 72% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2020-26213 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,386 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

🐹ktbs.dev/teler

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Impact

If you run teler inside a Docker container and encounter errors.Exit function, it will cause denial-of-service (SIGSEGV) because it doesn't get process ID and process group ID of teler properly to kills.

Specific Go Packages Affected

ktbs.dev/teler/pkg/errors

Patches

Upgrade to the >= 0.0.1 version.

Workarounds

N/A

References

https://github.com/kitabisa/teler/commit/ec6082049dba9e44a21f35fb7b123d42ce1a1a7e

For more information

If you have any questions or comments about this advisory:

Open an issue in Issues Section
Email us at [email protected]

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`ktbs.dev/teler`	all versions	0.0.1`go get ktbs.dev/teler@v0.0.1`

Affected Products

1 product · 1 configurations

Application

telerteler_project

< 0.0.1

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ktbs.dev/teler, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ktbs.dev/teler to 0.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-26213 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

### Impact If you run teler inside a Docker container and encounter `errors.Exit` function, it will cause denial-of-service (`SIGSEGV`) because it doesn't get process ID and process group ID of teler properly to kills. ### Specific Go Packages Affected ktbs.dev/teler/pkg/errors ### Patches Upgrade to the >= 0.0.1 version. ### Workarounds N/A ### References - https://github.com/kitabisa/teler/commit/ec6082049dba9e44a21f35fb7b123d42ce1a1a7e ### For more information If you have any questions or comments about this advisory: * Open an issue in [Issues Section](https://github.com/kitabisa/tele