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Public proof of conceptFix available

CVE-2021-22946

A public proof of concept exists; no exploitation attested.

  • Published2021-09-29
  • WeaknessCWE-319 · CWE-325

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A user can tell curl >= 7.20.0 and <= 7.78.0 to require a successful upgrade to TLS when speaking to an IMAP, POP3 or FTP server (`--ssl-reqd` on the command line or`CURLOPT_USE_SSL` set to `CURLUSESSL_CONTROL` or `CURLUSESSL_ALL` withlibcurl). This requirement could be bypassed if the server would return a properly crafted but perfectly legitimate response.This flaw would then make curl silently continue its operations **withoutTLS** contrary to the instructions and expectations, exposing possibly sensitive data in clear text over the network.

Timeline

dates in UTC
  1. 2021-09-2920:15CVE publishedNVD

Versions per branch

NVD
Oracle communications cloud native core network repository function
BranchAffectedFixed in
1.15= 1.15.0no fix published
1.15= 1.15.1no fix published
22.1= 22.1.0no fix published
22.2= 22.2.0no fix published
Debian debian linux
BranchAffectedFixed in
9.0= 9.0no fix published
10.0= 10.0no fix published
11.0= 11.0no fix published
Oracle peoplesoft enterprise peopletools
BranchAffectedFixed in
8.57= 8.57no fix published
8.58= 8.58no fix published
8.59= 8.59no fix published

26 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA1 product

As hackerone, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

  • https://github.com/curl/curl
    Affected
    • = curl 7.20.0 to and including 7.78.0no fix stated

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2022-12-19

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • curlUbuntu:Pro:16.04:LTSall versions · fixed in 7.47.0-1ubuntu2.19+esm1
  • curlUbuntu:Pro:14.04:LTSall versions · fixed in 7.35.0-1ubuntu2.20+esm8
  • curlUbuntu:22.04:LTSall versions · fixed in 7.74.0-1.3ubuntu2
  • curlUbuntu:20.04:LTSall versions · fixed in 7.68.0-1ubuntu2.7
  • curlUbuntu:18.04:LTSall versions · fixed in 7.58.0-2ubuntu3.15
  • curlSUSE:OpenStack Cloud Crowbar 9all versions · fixed in 7.60.0-4.30.1
  • curlSUSE:OpenStack Cloud 9all versions · fixed in 7.60.0-4.30.1
  • curlSUSE:Linux Enterprise Software Development Kit 12 SP5all versions · fixed in 7.60.0-11.28.1

53 more package ranges on OSV.dev

Vendor advisories

  • CVE-2021-22946 Red Hat Product Security105 products fixed · 13 known affected

    curl: Requirement to use TLS not properly enforced for IMAP, POP3, and FTP protocols

    rh-dotnet21-curl.src as a component of .NET Core 2.1 on Red Hat Enterprise Linux · rh-dotnet21-libcurl as a component of .NET Core 2.1 on Red Hat Enterprise Linux · rh-dotnet21-libcurl-devel as a component of .NET Core 2.1 on Red Hat Enterprise Linux · +10 more

  • ICSA-23-348-10 CISA5 known affected

    Siemens SIMATIC S7-1500

    SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) · SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) · +2 more

  • SSA-398330 Siemens ProductCERT5 known affected

    SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5

    SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= V3.1.0 < V3.1.5 · SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= V3.1.0 < V3.1.5 · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= V3.1.0 < V3.1.5 · +2 more

  • ICSA-23-194-01 CISA11 known affected

    Siemens RUGGEDCOM ROX

    RUGGEDCOM ROX MX5000 · RUGGEDCOM ROX MX5000RE · RUGGEDCOM ROX RX1400 · +8 more

  • SSA-146325 Siemens ProductCERT11 known affected

    SSA-146325: Multiple Vulnerabilities in RUGGEDCOM ROX before V2.16

    RUGGEDCOM ROX MX5000 · RUGGEDCOM ROX MX5000RE · RUGGEDCOM ROX RX1400 · +8 more

  • RHSA-2022:1354 Red Hat Product Security15 products fixed

    Red Hat Security Advisory: rh-dotnet31-curl security update

4 more advisories

Full record on NVD

Fix

  1. Vendor fix CISA ICSA-23-348-10 · 5 productsUpdate to V3.1.5 or later version
  2. Vendor fix Siemens ProductCERT SSA-398330 · 1 productUpdate to V3.1.5 or later version
  3. Vendor fix Siemens ProductCERT SSA-146325 · 11 productsUpdate to V2.16.0 or later version
  4. Vendor fix CISA ICSA-23-194-01 · 11 productsUpdate to V2.16.0 or later version
  5. Vendor fix Red Hat Product Security RHSA-2022:1354 · 15 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
  6. Vendor fix Siemens ProductCERT SSA-389290 · 1 productUpdate to V1.0.1.1 or later version

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Published
2021-09-29
Last Modified
2026-10-14
NVD status
Modified
GitHub Advisory
GHSA-3cmq-42w4-c529

Frequently asked questions

What is CVE-2021-22946?

A user can tell curl >= 7.20.0 and <= 7.78.0 to require a successful upgrade to TLS when speaking to an IMAP, POP3 or FTP server (`--ssl-reqd` on the command line or`CURLOPT_USE_SSL` set to `CURLUSESSL_CONTROL` or `CURLUSESSL_ALL` withlibcurl). This requirement could be bypassed if the server would return a properly crafted but perfectly legitimate response.This flaw would then make curl silently continue its operations **withoutTLS** contrary to the instructions and expectations, exposing possibly sensitive data in clear text over the network.

Is CVE-2021-22946 actively exploited?

A proof-of-concept exploit exists for CVE-2021-22946, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2021-22946?

CVE-2021-22946 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

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