In the Linux kernel, the following vulnerability has been resolved:
tee: fix NULL pointer dereference in tee_shm_put
tee_shm_put have NULL pointer dereference:
__optee_disable_shm_cache -->
shm = reg_pair_to_ptr(...);//shm maybe return NULL
tee_shm_free(shm); -->
tee_shm_put(shm);//crash
Add check in tee_shm_put to fix it.
panic log:
Unable to handle kernel paging request at virtual address 0000000000100cca
Mem abort info:
ESR = 0x0000000096000004
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x04: level 0 translation fault
Data abort info:
ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
CM = 0, WnR = 0, TnD = 0, TagAccess = 0
GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=0000002049d07000
[0000000000100cca] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 0000000096000004 [#1] SMP
CPU: 2 PID: 14442 Comm: systemd-sleep Tainted: P OE ------- ----
6.6.0-39-generic #38
Source Version: 938b255f6cb8817c95b0dd5c8c2944acfce94b07
Hardware name: greatwall GW-001Y1A-FTH, BIOS Great Wall BIOS V3.0
10/26/2022
pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : tee_shm_put+0x24/0x188
lr : tee_shm_free+0x14/0x28
sp : ffff001f98f9faf0
x29: ffff001f98f9faf0 x28: ffff0020df543cc0 x27: 0000000000000000
x26: ffff001f811344a0 x25: ffff8000818dac00 x24: ffff800082d8d048
x23: ffff001f850fcd18 x22: 0000000000000001 x21: ffff001f98f9fb88
x20: ffff001f83e76218 x19: ffff001f83e761e0 x18: 000000000000ffff
x17: 303a30303a303030 x16: 0000000000000000 x15: 0000000000000003
x14: 0000000000000001 x13: 0000000000000000 x12: 0101010101010101
x11: 0000000000000001 x10: 0000000000000001 x9 : ffff800080e08d0c
x8 : ffff001f98f9fb88 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
x2 : ffff001f83e761e0 x1 : 00000000ffff001f x0 : 0000000000100cca
Call trace:
tee_shm_put+0x24/0x188
tee_shm_free+0x14/0x28
__optee_disable_shm_cache+0xa8/0x108
optee_shutdown+0x28/0x38
platform_shutdown+0x28/0x40
device_shutdown+0x144/0x2b0
kernel_power_off+0x3c/0x80
hibernate+0x35c/0x388
state_store+0x64/0x80
kobj_attr_store+0x14/0x28
sysfs_kf_write+0x48/0x60
kernfs_fop_write_iter+0x128/0x1c0
vfs_write+0x270/0x370
ksys_write+0x6c/0x100
__arm64_sys_write+0x20/0x30
invoke_syscall+0x4c/0x120
el0_svc_common.constprop.0+0x44/0xf0
do_el0_svc+0x24/0x38
el0_svc+0x24/0x88
el0t_64_sync_handler+0x134/0x150
el0t_64_sync+0x14c/0x15
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
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). 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; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” 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