CVE-2021-39923
published 2021-11-19CVE-2021-39923: Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
PriorityP335high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.53%
72.1th percentile
Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
Affected
15 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | debian_linux | — | — |
| debian | debian_linux | — | — |
| debian | wireshark | < wireshark 3.6.0-1 (bookworm) | wireshark 3.6.0-1 (bookworm) |
| msrc | cbl2_wireshark_3.4.14-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| wireshark | wireshark | >= 0 < 3.4.10-0+deb11u1 | 3.4.10-0+deb11u1 |
| wireshark | wireshark | >= 0 < 3.6.0-1 | 3.6.0-1 |
| wireshark | wireshark | >= 0 < 3.6.0-1 | 3.6.0-1 |
| wireshark | wireshark | >= 0 < 3.6.0-1 | 3.6.0-1 |
| wireshark | wireshark | 3.2.0 – 3.2.17 | — |
| wireshark | wireshark | 3.4.0 – 3.4.9 | — |
| wireshark_foundation | wireshark | — | — |
| wireshark_foundation | wireshark | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_debian7.5HIGH
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
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GHSA
GHSA-v75m-35ph-56m2: NULL pointer exception in the IPPUSB dissector in Wireshark 3
ghsa_unreviewed·2021-11-20
CVE-2021-39923 [HIGH] CWE-476 GHSA-v75m-35ph-56m2: NULL pointer exception in the IPPUSB dissector in Wireshark 3
NULL pointer exception in the IPPUSB dissector in Wireshark 3.4.0 to 3.4.9 allows denial of service via packet injection or crafted capture file
OSV
CVE-2021-39923: Large loop in the PNRP dissector in Wireshark 3
osv·2021-11-19·CVSS 7.5
CVE-2021-39923 [HIGH] CVE-2021-39923: Large loop in the PNRP dissector in Wireshark 3
Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
Red Hat
wireshark: PNRP dissector large loop
vendor_redhat·2021-11-17·CVSS 7.5
CVE-2021-39923 [HIGH] CWE-400 wireshark: PNRP dissector large loop
wireshark: PNRP dissector large loop
Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
A flaw was found in Wireshark. A process failure consumes excessive CPU resources on crafted or malformed PNRP input and can cause a denial of service.
Package: wireshark (Red Hat Enterprise Linux 6) - Not affected
Package: wireshark (Red Hat Enterprise Linux 7) - Not affected
Package: wireshark (Red Hat Enterprise Linux 8) - Not affected
Package: wireshark (Red Hat Enterprise Linux 9) - Not affected
Microsoft
Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
vendor_msrc·2021-11-09·CVSS 7.5
CVE-2021-39923 [HIGH] CWE-834 Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
GitLab: G
Debian
CVE-2021-39923: wireshark - Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17...
vendor_debian·2021·CVSS 7.5
CVE-2021-39923 [HIGH] CVE-2021-39923: wireshark - Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17...
Large loop in the PNRP dissector in Wireshark 3.4.0 to 3.4.9 and 3.2.0 to 3.2.17 allows denial of service via packet injection or crafted capture file
Scope: local
bookworm: resolved (fixed in 3.6.0-1)
bullseye: resolved (fixed in 3.4.10-0+deb11u1)
forky: resolved (fixed in 3.6.0-1)
sid: resolved (fixed in 3.6.0-1)
trixie: resolved (fixed in 3.6.0-1)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39923.jsonhttps://gitlab.com/wireshark/wireshark/-/issues/17684https://lists.debian.org/debian-lts-announce/2021/12/msg00015.htmlhttps://www.debian.org/security/2021/dsa-5019https://www.wireshark.org/security/wnpa-sec-2021-11.htmlhttps://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39923.jsonhttps://gitlab.com/wireshark/wireshark/-/issues/17684https://lists.debian.org/debian-lts-announce/2021/12/msg00015.htmlhttps://www.debian.org/security/2021/dsa-5019https://www.wireshark.org/security/wnpa-sec-2021-11.html
2021-11-19
Published