CVE & CISA-KEV Catalog

CVE-2021-22898

LOWEPSS 91th pctl
3.1
CVSS v3
NVD

Description

curl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers. Due to a flaw in the option parser for sending NEW_ENV variables, libcurl could be made to pass on uninitialized data from a stack based buffer to the server, resulting in potentially revealing sensitive internal information to the server using a clear-text network protocol.

How to fix

Remediation Available
curlAmazon
Fixed in:0:7.61.1-12.amzn2.0.4
Fixed in:0:7.61.1-12.amzn2.0.4
Fixed in:0:7.61.1-12.amzn2.0.4
curl-debuginfoAmazon
Fixed in:0:7.61.1-12.amzn2.0.4
Fixed in:0:7.61.1-12.amzn2.0.4
Fixed in:0:7.61.1-12.amzn2.0.4
libcurlAmazon
Fixed in:0:7.61.1-12.amzn2.0.4
Fixed in:0:7.61.1-12.amzn2.0.4
Fixed in:0:7.61.1-12.amzn2.0.4
libcurl-develAmazon
Fixed in:0:7.61.1-12.amzn2.0.4
Fixed in:0:7.61.1-12.amzn2.0.4
Fixed in:0:7.61.1-12.amzn2.0.4
curlDebian
Fixed in:7.79.1-1CVE-2021-22898
Fixed in:7.79.1-1CVE-2021-22898
Fixed in:7.79.1-1CVE-2021-22898
curlUbuntu
Fixed in:7.35.0-1ubuntu2.20+esm14USN-5894-1

This Ubuntu release reached end-of-life on 2019-04-02.

Fixed in:7.47.0-1ubuntu2.19+esm3USN-5021-2

This Ubuntu release reached end-of-life on 2021-04-02.

Fixed in:7.47.0-1ubuntu2.19+esm7USN-5894-1

This Ubuntu release reached end-of-life on 2021-04-02.

Fixed in:7.58.0-2ubuntu3.14USN-5021-1

This Ubuntu release reached end-of-life on 2023-05-31. Extended security maintenance is available until 2028-04-01.

Fixed in:7.68.0-1ubuntu2.6USN-5021-1

This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.

libcurl3Ubuntu
Fixed in:7.35.0-1ubuntu2.20+esm14USN-5894-1

This Ubuntu release reached end-of-life on 2019-04-02.

Fixed in:7.47.0-1ubuntu2.19+esm7USN-5894-1

This Ubuntu release reached end-of-life on 2021-04-02.

Fixed in:7.47.0-1ubuntu2.19+esm3USN-5021-2

This Ubuntu release reached end-of-life on 2021-04-02.

libcurl3-gnutlsUbuntu
Fixed in:7.35.0-1ubuntu2.20+esm14USN-5894-1

This Ubuntu release reached end-of-life on 2019-04-02.

Fixed in:7.47.0-1ubuntu2.19+esm3USN-5021-2

This Ubuntu release reached end-of-life on 2021-04-02.

Fixed in:7.47.0-1ubuntu2.19+esm7USN-5894-1

This Ubuntu release reached end-of-life on 2021-04-02.

Fixed in:7.58.0-2ubuntu3.14USN-5021-1

This Ubuntu release reached end-of-life on 2023-05-31. Extended security maintenance is available until 2028-04-01.

Fixed in:7.68.0-1ubuntu2.6USN-5021-1

This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.

libcurl3-nssUbuntu
Fixed in:7.35.0-1ubuntu2.20+esm14USN-5894-1

This Ubuntu release reached end-of-life on 2019-04-02.

Fixed in:7.47.0-1ubuntu2.19+esm7USN-5894-1

This Ubuntu release reached end-of-life on 2021-04-02.

Fixed in:7.47.0-1ubuntu2.19+esm3USN-5021-2

This Ubuntu release reached end-of-life on 2021-04-02.

Fixed in:7.58.0-2ubuntu3.14USN-5021-1

This Ubuntu release reached end-of-life on 2023-05-31. Extended security maintenance is available until 2028-04-01.

Fixed in:7.68.0-1ubuntu2.6USN-5021-1

This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.

libcurl4Ubuntu
Fixed in:7.58.0-2ubuntu3.14USN-5021-1

This Ubuntu release reached end-of-life on 2023-05-31. Extended security maintenance is available until 2028-04-01.

Fixed in:7.68.0-1ubuntu2.6USN-5021-1

This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.

UniversalForwarderWindows application
Affected:9.0.0 9.0.6Fixed in:9.0.6Splunk, Inc.
Affected:8.2.0 8.2.12Fixed in:8.2.12Splunk, Inc.

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Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged

Impact

ConfidentialityLow
IntegrityNone
AvailabilityNone

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

Exploit Intelligence

4.51%probability of exploitation in 30 days
91stpercentile

High risk: more likely to be exploited than 91% of all known CVEs.

References

Related Vulnerabilities

Other CWE-200 (Information Exposure) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2024-24919High8.6100%KEV + Ransom-
CVE-2020-14181Medium5.3100%-Fix
CVE-2021-34429Medium5.399%-Fix
CVE-2018-11409Medium5.398%--
CVE-2021-41277Critical10.097%KEV-
CVE-2016-2183High7.596%-Fix

Common questions

How do I fix CVE-2021-22898?

Published advisories record a fix for 11 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2021-22898 being actively exploited?

Not that we know of. CVE-2021-22898 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 4.5% is the estimated probability that it will be exploited in the next 30 days. That is higher than 91% of all scored CVEs.

How severe is CVE-2021-22898?

CVE-2021-22898 has a CVSS v3 base score of 3.1, rated low. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2021-22898 affect?

Published advisories record a fix for curl (Amazon), curl-debuginfo (Amazon), libcurl (Amazon), libcurl-devel (Amazon), and 7 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-17.