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CVE-2021-22947

When curl >= 7.20.0 and <= 7.78.0 connects to an IMAP or POP3 server to retrieve data using STARTTLS to upgrade to TLS security, the server can respond and send back multiple responses at once that...

Published: Sep 29, 2021Updated: Apr 16, 2026 Sources: CVE List NVD BDU csafCWE-310
NVD MITRE
5.9CVSSMEDIUM
EPSS Score
2.8%
Top 15.4%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available

Description

Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the firmware version >= V3.1.0 and < V3.1.5 for the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP (incl. SIPLUS variant). These GNU/Linux vulnerabilities have been externally identified. Siemens has released new versions for the affected products and recommends to update to the latest versions. Note: This SSA advises vulnerabilities for firmware version V3.1 only; for versions < V3.1 refer to Siemens Security Bulletin SSB-439005 ( https://cert-portal.siemens.com/productcert/html/ssb-439005.html).

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:NI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-310CWE-345

Affected Products

curlhaxxOSS Libraries
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
debian linuxdebian
On-premOS
Operating Systems / linux-distro
cloud backupnetappHardware Firmware
clustered data ontapnetappHardware Firmware
haxxoss-projectSEOSS Librariesaka haxx.se
fedoraprojectoss-projectUSOperating Systemsaka fedora project
debianoss-projectGBOperating Systemsaka debian gnu/linux
netappcommercialUSHardware Firmware
and 32 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://cert-portal.siemens.com/productcert/csaf/ssa-398330.json
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-398330.html
cert-portal.siemens.com
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2023/icsa-23-348-10.json
raw.githubusercontent.com
and 36 more references View all →

Timeline

Published
Sep 29, 2021
Last Updated
Apr 16, 2026

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