Submit #916219: Memcached 1.6.41 > 1.6.43 Out-of-Bounds Readinfo

TitleMemcached 1.6.41 > 1.6.43 Out-of-Bounds Read
DescriptionA pre-authentication remote denial-of-service vulnerability affects memcached 1.6.41 through 1.6.43 when started with ASCII authentication (-Y <authfile>). An unauthenticated client can trigger a crash by sending three newline bytes (\n\n\n) immediately after connecting. The authentication path forwards an empty line to the vendored mcmc tokenizer without validating that the token length is non-zero. Because _mcmc_tokenize_meta() assumes an input length of at least two bytes, it performs out-of-bounds pointer arithmetic and enters an unbounded scan that ultimately dereferences unmapped memory, causing the memcached process to terminate with SIGSEGV.
Source⚠️ https://protectiv.ph/research/memcached-asciiauth-empty-line-dos
User
 Ebfe7001d27b27064356271ddfb15d59 (UID 100393)
Submission08/05/2026 16:06 (1 month ago)
Moderation09/13/2026 07:24 (1 month later)
StatusDuplicate
VulDB entry403231 [memcached 1.6.41/1.6.42/1.6.43 mcmc Tokenizer proto_text.c try_read_command_asciiauth out-of-bounds]
Points0

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