DEBIAN-CVE-2025-39677

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Source
https://security-tracker.debian.org/tracker/CVE-2025-39677
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-39677.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2025-39677
Upstream
Published
2025-09-05T18:15:44Z
Modified
2026-09-01T20:05:49Z
Severity
  • 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

In the Linux kernel, the following vulnerability has been resolved: net/sched: Fix backlog accounting in qdisc_dequeue_internal This issue applies for the following qdiscs: hhf, fq, fq_codel, and fq_pie, and occurs in their change handlers when adjusting to the new limit. The problem is the following in the values passed to the subsequent qdisc_tree_reduce_backlog call given a tbf parent: When the tbf parent runs out of tokens, skbs of these qdiscs will be placed in gso_skb. Their peek handlers are qdisc_peek_dequeued, which accounts for both qlen and backlog. However, in the case of qdisc_dequeue_internal, ONLY qlen is accounted for when pulling from gso_skb. This means that these qdiscs are missing a qdisc_qstats_backlog_dec when dropping packets to satisfy the new limit in their change handlers. One can observe this issue with the following (with tc patched to support a limit of 0): export TARGET=fq tc qdisc del dev lo root tc qdisc add dev lo root handle 1: tbf rate 8bit burst 100b latency 1ms tc qdisc replace dev lo handle 3: parent 1:1 $TARGET limit 1000 echo ''; echo 'add child'; tc -s -d qdisc show dev lo ping -I lo -f -c2 -s32 -W0.001 127.0.0.1 2>&1 >/dev/null echo ''; echo 'after ping'; tc -s -d qdisc show dev lo tc qdisc change dev lo handle 3: parent 1:1 $TARGET limit 0 echo ''; echo 'after limit drop'; tc -s -d qdisc show dev lo tc qdisc replace dev lo handle 2: parent 1:1 sfq echo ''; echo 'post graft'; tc -s -d qdisc show dev lo The second to last show command shows 0 packets but a positive number (74) of backlog bytes. The problem becomes clearer in the last show command, where qdisc_purge_queue triggers qdisc_tree_reduce_backlog with the positive backlog and causes an underflow in the tbf parent's backlog (4096 Mb instead of 0). To fix this issue, the codepath for all clients of qdisc_dequeue_internal has been simplified: codel, pie, hhf, fq, fq_pie, and fq_codel. qdisc_dequeue_internal handles the backlog adjustments for all cases that do not directly use the dequeue handler. The old fq_codel_change limit adjustment loop accumulated the arguments to the subsequent qdisc_tree_reduce_backlog call through the cstats field. However, this is confusing and error prone as fq_codel_dequeue could also potentially mutate this field (which qdisc_dequeue_internal calls in the non gso_skb case), so we have unified the code here with other qdiscs.

References

Affected packages

Debian:12 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

6.*
6.1.27-1
6.1.37-1
6.1.38-1
6.1.38-2~bpo11+1
6.1.38-2
6.1.38-3
6.1.38-4~bpo11+1
6.1.38-4
6.1.52-1
6.1.55-1~bpo11+1
6.1.55-1
6.1.64-1
6.1.66-1
6.1.67-1
6.1.69-1~bpo11+1
6.1.69-1
6.1.76-1~bpo11+1
6.1.76-1
6.1.82-1
6.1.85-1
6.1.90-1~bpo11+1
6.1.90-1
6.1.94-1~bpo11+1
6.1.94-1
6.1.98-1
6.1.99-1
6.1.106-1
6.1.106-2
6.1.106-3
6.1.112-1
6.1.115-1
6.1.119-1
6.1.123-1
6.1.124-1
6.1.128-1
6.1.129-1
6.1.133-1
6.1.135-1
6.1.137-1
6.1.139-1
6.1.140-1
6.1.147-1
6.1.148-1
6.1.153-1
6.1.158-1
6.1.159-1
6.1.162-1
6.1.164-1
6.1.170-1
6.1.170-2
6.1.170-3
6.1.172-1
6.1.174-1
6.1.176-1
6.1.177-1
6.1.180-1
6.3.1-1~exp1
6.3.2-1~exp1
6.3.4-1~exp1
6.3.5-1~exp1
6.3.7-1~bpo12+1
6.3.7-1
6.3.11-1
6.4~rc6-1~exp1
6.4~rc7-1~exp1
6.4.1-1~exp1
6.4.4-1~bpo12+1
6.4.4-1
6.4.4-2
6.4.4-3~bpo12+1
6.4.4-3
6.4.11-1
6.4.13-1
6.5~rc4-1~exp1
6.5~rc6-1~exp1
6.5~rc7-1~exp1
6.5.1-1~exp1
6.5.3-1~bpo12+1
6.5.3-1
6.5.6-1
6.5.8-1
6.5.10-1~bpo12+1
6.5.10-1
6.5.13-1
6.6.3-1~exp1
6.6.4-1~exp1
6.6.7-1~exp1
6.6.8-1
6.6.9-1
6.6.11-1
6.6.13-1~bpo12+1
6.6.13-1
6.6.15-1
6.6.15-2
6.7-1~exp1
6.7.1-1~exp1
6.7.4-1~exp1
6.7.7-1
6.7.9-1
6.7.9-2
6.7.12-1~bpo12+1
6.7.12-1
6.8.9-1
6.8.11-1
6.8.12-1~bpo12+1
6.8.12-1
6.9.2-1~exp1
6.9.7-1~bpo12+1
6.9.7-1
6.9.8-1
6.9.9-1
6.9.10-1~bpo12+1
6.9.10-1
6.9.11-1
6.9.12-1
6.10-1~exp1
6.10.1-1~exp1
6.10.3-1
6.10.4-1
6.10.6-1~bpo12+1
6.10.6-1
6.10.7-1
6.10.9-1
6.10.11-1~bpo12+1
6.10.11-1
6.10.12-1
6.11~rc4-1~exp1
6.11~rc5-1~exp1
6.11-1~exp1
6.11.2-1
6.11.4-1
6.11.5-1~bpo12+1
6.11.5-1
6.11.6-1
6.11.7-1
6.11.9-1
6.11.10-1~bpo12+1
6.11.10-1
6.12~rc6-1~exp1
6.12.3-1
6.12.5-1
6.12.6-1
6.12.8-1
6.12.9-1~bpo12+1
6.12.9-1
6.12.9-1+alpha
6.12.10-1
6.12.11-1
6.12.11-1+alpha
6.12.11-1+alpha.1
6.12.12-1~bpo12+1
6.12.12-1
6.12.13-1
6.12.15-1
6.12.16-1
6.12.17-1
6.12.19-1
6.12.20-1
6.12.21-1
6.12.22-1~bpo12+1
6.12.22-1
6.12.25-1
6.12.27-1~bpo12+1
6.12.27-1
6.12.29-1
6.12.30-1~bpo12+1
6.12.30-1
6.12.31-1
6.12.32-1~bpo12+1
6.12.32-1
6.12.33-1~bpo12+1
6.12.33-1
6.12.35-1~bpo12+1
6.12.35-1
6.12.37-1
6.12.38-1~bpo12+1
6.12.38-1
6.12.41-1
6.12.43-1~bpo12+1
6.12.43-1
6.12.48-1
6.12.57-1~bpo12+1
6.12.57-1
6.12.63-1~bpo12+1
6.12.63-1
6.12.69-1~bpo12+1
6.12.69-1
6.12.73-1~bpo12+1
6.12.73-1
6.12.74-1
6.12.74-2~bpo12+1
6.12.74-2
6.12.85-1~bpo12+1
6.12.85-1
6.12.86-1~bpo12+1
6.12.86-1
6.12.88-1~bpo12+1
6.12.88-1
6.12.90-1~bpo12+1
6.12.90-1
6.12.90-2~bpo12+1
6.12.90-2
6.12.94-1~bpo12+1
6.12.94-1
6.12.95-1~bpo12+1
6.12.95-1
6.12.96-1
6.12.100-1
6.12.101-1
6.12.105-1
6.12.107-1
6.13~rc6-1~exp1
6.13~rc7-1~exp1
6.13.2-1~exp1
6.13.3-1~exp1
6.13.4-1~exp1
6.13.5-1~exp1
6.13.6-1~exp1
6.13.7-1~exp1
6.13.8-1~exp1
6.13.9-1~exp1
6.13.10-1~exp1
6.13.11-1~exp1
6.14.3-1~exp1
6.14.5-1~exp1
6.14.6-1~exp1
6.15~rc7-1~exp1
6.15-1~exp1
6.15.1-1~exp1
6.15.2-1~exp1
6.15.3-1~exp1
6.15.4-1~exp1
6.15.5-1~exp1
6.15.6-1~exp1
6.16~rc7-1~exp1
6.16-1~exp1
6.16.1-1~exp1
6.16.3-1~bpo13+1
6.16.3-1
6.16.5-1
6.16.6-1
6.16.7-1
6.16.8-1
6.16.9-1
6.16.10-1
6.16.11-1
6.16.12-1~bpo13+1
6.16.12-1
6.16.12-2
6.17.2-1~exp1
6.17.5-1~exp1
6.17.6-1
6.17.7-1
6.17.7-2
6.17.8-1~bpo13+1
6.17.8-1
6.17.9-1
6.17.10-1
6.17.11-1
6.17.12-1
6.17.13-1~bpo13+1
6.17.13-1
6.18~rc4-1~exp1
6.18~rc4-1~exp2
6.18~rc5-1~exp1
6.18~rc6-1~exp1
6.18~rc7-1~exp1
6.18.1-1~exp1
6.18.2-1~exp1
6.18.3-1
6.18.5-1~bpo13+1
6.18.5-1
6.18.8-1
6.18.9-1~bpo13+1
6.18.9-1
6.18.10-1
6.18.12-1~bpo13+1
6.18.12-1
6.18.13-1
6.18.14-1
6.18.15-1~bpo13+1
6.18.15-1
6.19~rc4-1~exp1
6.19~rc5-1~exp1
6.19~rc6-1~exp1
6.19~rc7-1~exp1
6.19~rc8-1~exp1
6.19-1~exp1
6.19.2-1~exp1
6.19.3-1~exp1
6.19.4-1~exp1
6.19.5-1~exp1
6.19.6-1
6.19.6-2~bpo13+1
6.19.6-2
6.19.8-1~bpo13+1
6.19.8-1
6.19.10-1~bpo13+1
6.19.10-1
6.19.11-1~bpo13+1
6.19.11-1
6.19.12-1
6.19.13-1~bpo13+1
6.19.13-1
6.19.14-1~bpo13+1
6.19.14-1
7.*
7.0-1~exp1
7.0.1-1~exp1
7.0.3-1
7.0.4-1~bpo13+1
7.0.4-1
7.0.7-1~bpo13+1
7.0.7-1
7.0.9-1~bpo13+1
7.0.9-1
7.0.10-1~bpo13+1
7.0.10-1
7.0.12-1
7.0.12-2~bpo13+1
7.0.12-2
7.0.13-1~bpo13+1
7.0.13-1
7.0.14-1
7.1~rc2-1~exp1
7.1~rc3-1~exp1
7.1~rc4-1~exp1
7.1~rc4-1~exp2
7.1~rc5-1~exp1
7.1~rc7-1~exp1
7.1.1-1~exp1
7.1.2-1~exp1
7.1.3-1~bpo13+1
7.1.3-1
7.1.3-1+sunvdc
7.1.4-1
7.1.5-1
7.1.6-1
7.1.7-1~bpo13+1
7.1.7-1
7.1.8-1~bpo13+1
7.1.8-1
7.1.8-2
7.1.9-1
7.1.9-1+sparc64
7.1.10-1
7.1.12-1
7.2~rc3-1~exp1
7.2~rc5-1~exp1
7.2~rc7-1~exp1
7.2.2-1~exp1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-39677.json"

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

6.*
6.12.38-1
6.12.41-1
6.12.43-1~bpo12+1
6.12.43-1
6.12.48-1
6.12.57-1~bpo12+1
6.12.57-1
6.12.63-1~bpo12+1
6.12.63-1
6.12.69-1~bpo12+1
6.12.69-1
6.12.73-1~bpo12+1
6.12.73-1
6.12.74-1
6.12.74-2~bpo12+1
6.12.74-2
6.12.85-1~bpo12+1
6.12.85-1
6.12.86-1~bpo12+1
6.12.86-1
6.12.88-1~bpo12+1
6.12.88-1
6.12.90-1~bpo12+1
6.12.90-1
6.12.90-2~bpo12+1
6.12.90-2
6.12.94-1~bpo12+1
6.12.94-1
6.12.95-1~bpo12+1
6.12.95-1
6.12.96-1
6.12.100-1
6.12.101-1
6.12.105-1
6.12.107-1
6.13~rc6-1~exp1
6.13~rc7-1~exp1
6.13.2-1~exp1
6.13.3-1~exp1
6.13.4-1~exp1
6.13.5-1~exp1
6.13.6-1~exp1
6.13.7-1~exp1
6.13.8-1~exp1
6.13.9-1~exp1
6.13.10-1~exp1
6.13.11-1~exp1
6.14.3-1~exp1
6.14.5-1~exp1
6.14.6-1~exp1
6.15~rc7-1~exp1
6.15-1~exp1
6.15.1-1~exp1
6.15.2-1~exp1
6.15.3-1~exp1
6.15.4-1~exp1
6.15.5-1~exp1
6.15.6-1~exp1
6.16~rc7-1~exp1
6.16-1~exp1
6.16.1-1~exp1
6.16.3-1~bpo13+1
6.16.3-1
6.16.5-1
6.16.6-1
6.16.7-1
6.16.8-1
6.16.9-1
6.16.10-1
6.16.11-1
6.16.12-1~bpo13+1
6.16.12-1
6.16.12-2
6.17.2-1~exp1
6.17.5-1~exp1
6.17.6-1
6.17.7-1
6.17.7-2
6.17.8-1~bpo13+1
6.17.8-1
6.17.9-1
6.17.10-1
6.17.11-1
6.17.12-1
6.17.13-1~bpo13+1
6.17.13-1
6.18~rc4-1~exp1
6.18~rc4-1~exp2
6.18~rc5-1~exp1
6.18~rc6-1~exp1
6.18~rc7-1~exp1
6.18.1-1~exp1
6.18.2-1~exp1
6.18.3-1
6.18.5-1~bpo13+1
6.18.5-1
6.18.8-1
6.18.9-1~bpo13+1
6.18.9-1
6.18.10-1
6.18.12-1~bpo13+1
6.18.12-1
6.18.13-1
6.18.14-1
6.18.15-1~bpo13+1
6.18.15-1
6.19~rc4-1~exp1
6.19~rc5-1~exp1
6.19~rc6-1~exp1
6.19~rc7-1~exp1
6.19~rc8-1~exp1
6.19-1~exp1
6.19.2-1~exp1
6.19.3-1~exp1
6.19.4-1~exp1
6.19.5-1~exp1
6.19.6-1
6.19.6-2~bpo13+1
6.19.6-2
6.19.8-1~bpo13+1
6.19.8-1
6.19.10-1~bpo13+1
6.19.10-1
6.19.11-1~bpo13+1
6.19.11-1
6.19.12-1
6.19.13-1~bpo13+1
6.19.13-1
6.19.14-1~bpo13+1
6.19.14-1
7.*
7.0-1~exp1
7.0.1-1~exp1
7.0.3-1
7.0.4-1~bpo13+1
7.0.4-1
7.0.7-1~bpo13+1
7.0.7-1
7.0.9-1~bpo13+1
7.0.9-1
7.0.10-1~bpo13+1
7.0.10-1
7.0.12-1
7.0.12-2~bpo13+1
7.0.12-2
7.0.13-1~bpo13+1
7.0.13-1
7.0.14-1
7.1~rc2-1~exp1
7.1~rc3-1~exp1
7.1~rc4-1~exp1
7.1~rc4-1~exp2
7.1~rc5-1~exp1
7.1~rc7-1~exp1
7.1.1-1~exp1
7.1.2-1~exp1
7.1.3-1~bpo13+1
7.1.3-1
7.1.3-1+sunvdc
7.1.4-1
7.1.5-1
7.1.6-1
7.1.7-1~bpo13+1
7.1.7-1
7.1.8-1~bpo13+1
7.1.8-1
7.1.8-2
7.1.9-1
7.1.9-1+sparc64
7.1.10-1
7.1.12-1
7.2~rc3-1~exp1
7.2~rc5-1~exp1
7.2~rc7-1~exp1
7.2.2-1~exp1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-39677.json"

Debian:14 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
6.16.5-1

Affected versions

6.*
6.12.38-1
6.12.41-1
6.12.43-1~bpo12+1
6.12.43-1
6.12.48-1
6.12.57-1~bpo12+1
6.12.57-1
6.12.63-1~bpo12+1
6.12.63-1
6.12.69-1~bpo12+1
6.12.69-1
6.12.73-1~bpo12+1
6.12.73-1
6.12.74-1
6.12.74-2~bpo12+1
6.12.74-2
6.12.85-1~bpo12+1
6.12.85-1
6.12.86-1~bpo12+1
6.12.86-1
6.12.88-1~bpo12+1
6.12.88-1
6.12.90-1~bpo12+1
6.12.90-1
6.12.90-2~bpo12+1
6.12.90-2
6.12.94-1~bpo12+1
6.12.94-1
6.12.95-1~bpo12+1
6.12.95-1
6.12.96-1
6.12.100-1
6.12.101-1
6.12.105-1
6.12.107-1
6.13~rc6-1~exp1
6.13~rc7-1~exp1
6.13.2-1~exp1
6.13.3-1~exp1
6.13.4-1~exp1
6.13.5-1~exp1
6.13.6-1~exp1
6.13.7-1~exp1
6.13.8-1~exp1
6.13.9-1~exp1
6.13.10-1~exp1
6.13.11-1~exp1
6.14.3-1~exp1
6.14.5-1~exp1
6.14.6-1~exp1
6.15~rc7-1~exp1
6.15-1~exp1
6.15.1-1~exp1
6.15.2-1~exp1
6.15.3-1~exp1
6.15.4-1~exp1
6.15.5-1~exp1
6.15.6-1~exp1
6.16~rc7-1~exp1
6.16-1~exp1
6.16.1-1~exp1
6.16.3-1~bpo13+1
6.16.3-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-39677.json"