medium CVSS 5.5

CVE-2023-52708·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: mmc: mmc_spi: fix error handling in mmc_spi_probe() If mmc_add_host() fails, it doesn't need to call mmc_remove_host(), or it will cause null-ptr-deref, because of deleting a not added device in mmc_remove_host(). To fix this, goto label 'fail_glue_init', if mmc_add_host() fails, and change the label 'fail_add_host' to 'fail_gpiod_request'.

Severity
medium
Software
Kernel
Fixed in
6.1.13
Published
2024-05-21

Affected versions

From: 5.16

Until: 6.1.13

Fixed in: 6.1.13

How to fix this CVE

Update your Linux kernel to version 6.1.13 or later to resolve a device management error in the mmc_spi driver that can cause kernel crashes. This fix corrects the error handling path when MMC host registration fails, preventing null pointer dereference during cleanup. Systems running kernel versions 5.16 through 6.1.12 with SPI-based MMC devices should prioritize this update.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your kernel version with `uname -r` and compare against the affected range (5.16 to 6.1.12)
  2. Step 2: Verify if mmc_spi module is loaded: `lsmod | grep mmc_spi` or `modinfo mmc_spi`
  3. Step 3: Search kernel logs for mmc_spi initialization failures: `dmesg | grep -i 'mmc_spi\|mmc_add_host'` or `journalctl -k | grep -i 'mmc_spi'`
  4. Step 4: After patching, confirm the new kernel version: `uname -r` should show 6.1.13 or later, and `dmesg | grep -i 'mmc_spi'` should show successful device initialization

FAQ

What is CVE-2023-52708?

CVE-2023-52708 is a kernel bug in the mmc_spi driver where incorrect error handling during device registration leads to a null pointer dereference, potentially causing kernel panics on systems with SPI-connected MMC/SD cards.

Is CVE-2023-52708 being actively exploited?

No, this vulnerability is not listed in CISA's Known Exploited Vulnerabilities catalog and no public exploits are available. However, it can be triggered locally by unprivileged users with access to SPI MMC devices.

What versions of Kernel are affected by CVE-2023-52708?

Linux kernel versions 5.16.0 through 6.1.12 are affected. The vulnerability was fixed in kernel 6.1.13 and backported to stable branches.

How do I check if my server is vulnerable to CVE-2023-52708?

Run `uname -r` and check if your version falls between 5.16 and 6.1.12. Additionally, verify the mmc_spi module is present with `grep -i mmc_spi /lib/modules/$(uname -r)/modules.builtin` or `lsmod | grep mmc_spi`.

Does Defensia detect CVE-2023-52708?

Yes — Defensia's CVE advisory scanner compares installed kernel versions against the NVD database. If a vulnerable kernel version is detected on your monitored servers, CVE-2023-52708 will appear in your dashboard with remediation steps and affected module information.

Related Kernel CVEs

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CVE-2026-100075CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: RDMA/srpt: Fix srpt_alloc_rw_ctxs() unwind counters When srpt_alloc_rw_ctxs() fails partway through a multi-buffer indirect descriptor, the unwind path destroys RDMA contexts but leaves stale n_rw_ctx and n_rdma values (and a dangling rw_ctxs pointer). Later sq_wr_avail accounting in srpt_queue_response() or srpt_write_pending() can then subtract the wrong number of send queue credits. Reset the counters and clear rw_ctxs after freeing the heap allocation before returning an error.
CVE-2026-64035CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: igc: set tx buffer type for SMD frames Sashiko pointed out that igc_fpe_init_smd_frame() initializes igc_tx_buffer fields for an SMD skb, but does not set the buffer type: https://sashiko.dev/#/patchset/20260415025226.114115-1-kohei%40enjuk.jp Since igc_tx_buffer entries are reused, a stale XDP or XSK type can remain and make TX completion use the wrong cleanup path. Set the buffer type to IGC_TX_BUFFER_TYPE_SKB.
CVE-2026-64007CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: netfilter: synproxy: refresh tcphdr after skb_ensure_writable synproxy_tstamp_adjust() rewrites the TCP timestamp option in place and then patches the TCP checksum via inet_proto_csum_replace4() on the caller-supplied tcphdr pointer. Both ipv4_synproxy_hook() and ipv6_synproxy_hook() obtain that pointer with skb_header_pointer() before calling in, so it may either alias skb->head directly or point at the caller's on-stack _tcph buffer. Between obtaining the pointer and using it, the function calls skb_ensure_writable(skb, optend), which on a cloned or non-linear skb invokes pskb_expand_head() and frees the old skb->head. After that point the cached th is stale: caller (ipv[46]_synproxy_hook) th = skb_header_pointer(skb, ..., &_tcph) synproxy_tstamp_adjust(skb, protoff, th, ...) skb_ensure_writable(skb, optend) pskb_expand_head() /* kfree(old skb->head) */ ... inet_proto_csum_replace4(&th->check, ...) /* writes into freed head, or into the caller's stack copy leaving the on-wire checksum stale */ The option bytes are written through skb->data and are fine; only the checksum update goes through th and so lands in the wrong place. The result is either a write into freed slab memory or a packet leaving with a checksum that does not match its payload. Fix by re-deriving th from skb->data + protoff immediately after skb_ensure_writable() succeeds, so the subsequent checksum update targets the linear, writable header.

References

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