CVE-2023-53326powerpc: Don't try to copy PPR for task with NULL pt_regs
- 5.5MediumCVSS base score
- 0.15%Exploitation in 30 daysEPSS · top 96% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: powerpc: Don't try to copy PPR for task with NULL pt_regs powerpc sets up PF_KTHREAD and PF_IO_WORKER with a NULL pt_regs, which from my (arguably very short) checking is not commonly done for other archs. This is fine, except when PF_IO_WORKER's have been created and the task does something that causes a coredump to be generated. Then we get this crash: Kernel attempted to read user page (160) - exploit attempt? (uid: 1000) BUG: Kernel NULL pointer dereference on read at 0x00000160 Faulting instruction address: 0xc0000000000c3a60 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=32 NUMA pSeries Modules linked in: bochs drm_vram_helper drm_kms_helper xts binfmt_misc ecb ctr syscopyarea sysfillrect cbc sysimgblt drm_ttm_helper aes_generic ttm sg libaes evdev joydev virtio_balloon vmx_crypto gf128mul drm dm_mod fuse loop configfs drm_panel_orientation_quirks ip_tables x_tables autofs4 hid_generic usbhid hid xhci_pci xhci_hcd usbcore usb_common sd_mod CPU: 1 PID: 1982 Comm: ppc-crash Not tainted 6.3.0-rc2+ #88 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries NIP: c0000000000c3a60 LR: c000000000039944 CTR: c0000000000398e0 REGS: c0000000041833b0 TRAP: 0300 Not tainted (6.3.0-rc2+) MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 88082828 XER: 200400f8 ... NIP memcpy_power7+0x200/0x7d0 LR ppr_get+0x64/0xb0 Call Trace: ppr_get+0x40/0xb0 (unreliable) __regset_get+0x180/0x1f0 regset_get_alloc+0x64/0x90 elf_core_dump+0xb98/0x1b60 do_coredump+0x1c34/0x24a0 get_signal+0x71c/0x1410 do_notify_resume+0x140/0x6f0 interrupt_exit_user_prepare_main+0x29c/0x320 interrupt_exit_user_prepare+0x6c/0xa0 interrupt_return_srr_user+0x8/0x138 Because ppr_get() is trying to copy from a PF_IO_WORKER with a NULL pt_regs. Check for a valid pt_regs in both ppc_get/ppr_set, and return an error if not set. The actual error value doesn't seem to be important here, so just pick -EINVAL. [mpe: Trim oops in change log, add Fixes & Cc stable]
Timeline
ID reserved
By Linux
Published
- 8 months later
· 8 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.15% · top 96% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
- affected fa439810cc1b3c927ec24ede17d02467e1b143a1 – < 80a4200d51e5a7e046f4a90f5faa5bafd5a60c58
- affected fa439810cc1b3c927ec24ede17d02467e1b143a1 – < 7624973bc15b76d000e8e6f9b8080fcb76d36595
- affected fa439810cc1b3c927ec24ede17d02467e1b143a1 – < 064a1c7b0f8403260d77627e62424a72ca26cee2
- affected fa439810cc1b3c927ec24ede17d02467e1b143a1 – < 01849382373b867ddcbe7536b9dfa89f3bcea60e
- affected fa439810cc1b3c927ec24ede17d02467e1b143a1 – < fd7276189450110ed835eb0a334e62d2f1c4e3be
- affected 4.8
- unaffected < 4.8
- unaffected 5.10.177 – ≤ 5.10.*
- unaffected 5.15.106 – ≤ 5.15.*
- unaffected 6.1.23 – ≤ 6.1.*
- unaffected 6.2.10 – ≤ 6.2.*
- unaffected 6.3 – ≤ *
References
References5
- https://git.kernel.org/stable/c/80a4200d51e5a7e046f4a90f5faa5bafd5a60c58 (opens in a new tab)
- https://git.kernel.org/stable/c/7624973bc15b76d000e8e6f9b8080fcb76d36595 (opens in a new tab)
- https://git.kernel.org/stable/c/064a1c7b0f8403260d77627e62424a72ca26cee2 (opens in a new tab)
- https://git.kernel.org/stable/c/01849382373b867ddcbe7536b9dfa89f3bcea60e (opens in a new tab)
- https://git.kernel.org/stable/c/fd7276189450110ed835eb0a334e62d2f1c4e3be (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-59935 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-53326)Record last updated .