In the Linux kernel, the following vulnerability has been resolved:
tls: Purge async_hold in tls_decrypt_async_wait()
The async_hold queue pins encrypted input skbs while
the AEAD engine references their scatterlist data. Once
tls_decrypt_async_wait() returns, every AEAD operation
has completed and the engine no longer references those
skbs, so they can be freed unconditionally.
A subsequent patch adds batch async decryption to
tls_sw_read_sock(), introducing a new call site that
must drain pending AEAD operations and release held
skbs. Move __skb_queue_purge(&ctx->async_hold) into
tls_decrypt_async_wait() so the purge is centralized
and every caller -- recvmsg's drain path, the -EBUSY
fallback in tls_do_decryption(), and the new read_sock
batch path -- releases held skbs on synchronization
without each site managing the purge independently.
This fixes a leak when tls_strp_msg_hold() fails part-way through,
after having added some cloned skbs to the async_hold
queue. tls_decrypt_sg() will then call tls_decrypt_async_wait() to
process all pending decrypts, and drop back to synchronous mode, but
tls_sw_recvmsg() only flushes the async_hold queue when one record has
been processed in "fully-async" mode, which may not be the case here.
[[email protected]: added leak comment]
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.4% within 30 daysSource: FIRST EPSS. FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it