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Critical 9.1Published Sep 23, 2021

CVE-2021-22945When sending data to an MQTT server, libcurl <= 7.73.0 and 7.78.0 could in some circumstances erroneously keep a pointer to an already freed memory area and both use that again in a subsequent call t…

Updated under an hour ago ()

Does this affect you?

It affects Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP and 19 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

When sending data to an MQTT server, libcurl <= 7.73.0 and 7.78.0 could in some circumstances erroneously keep a pointer to an already freed memory area and both use that again in a subsequent call to send data and also free it *again*.

CVSS
9.1 CRITICAL (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Weakness (CWE)
CWE-415
Known exploited
Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days)
Not loaded for this CVE
Assigned by
hackerone
NVD analysis
Modified
Record last updated
Oct 14, 2026
First seen by InfoSec Signals
Oct 14, 2026

Affected products

Affected products
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)
from V3.1.0 before V3.1.5
CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)
from V3.1.0 before V3.1.5
CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP
siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)
from V3.1.0 before V3.1.5
CISA ADP
haxx libcurl
haxx:libcurl
from 7.73.0 through 7.78.0
NVD
fedoraproject fedora
fedoraproject:fedora
33; 35
NVD
netapp cloud_backup
netapp:cloud_backup
all versions
NVD
netapp clustered_data_ontap
netapp:clustered_data_ontap
all versions
NVD
oracle mysql_server
oracle:mysql_server
from 5.7.0 through 5.7.35; from 8.0.0 through 8.0.26
NVD
netapp h300s_firmware
netapp:h300s_firmware
all versions
NVD
netapp h500s_firmware
netapp:h500s_firmware
all versions
NVD
netapp h700s_firmware
netapp:h700s_firmware
all versions
NVD
netapp h300e_firmware
netapp:h300e_firmware
all versions
NVD
netapp h500e_firmware
netapp:h500e_firmware
all versions
NVD
netapp h700e_firmware
netapp:h700e_firmware
all versions
NVD
netapp h410s_firmware
netapp:h410s_firmware
all versions
NVD
netapp solidfire_baseboard_management_controller_firmware
netapp:solidfire_baseboard_management_controller_firmware
all versions
NVD
apple macos
apple:macos
from 12.0.0 before 12.3
NVD
siemens sinec_ins
siemens:sinec_ins
before 1.0.1.1
NVD
debian debian_linux
debian:debian_linux
11.0
NVD
splunk universal_forwarder
splunk:universal_forwarder
from 8.2.0 before 8.2.12; from 9.0.0 before 9.0.6; 9.1.0
NVD

References

  • exploit, patch, third-party-advisory
  • vendor-advisory, mailing-list, third-party-advisory
  • patch, third-party-advisory
  • third-party-advisory
  • vendor-advisory, mailing-list, third-party-advisory
  • patch, third-party-advisory
  • third-party-advisory
  • mailing-list, third-party-advisory
  • vendor-advisory, third-party-advisory
  • vendor-advisory, third-party-advisory

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.

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