libcroco 0.6.12 – Denial of Service
libcroco multiple vulnerabilities ================ Author : qflb.wu =============== Introduction: ============= Libcroco is a standalone css2 parsing and manipulation library. The parser provides a low level event driven SAC like api and a css object model like api. Libcroco provides a CSS2 selection engine and an experimental xml/css rendering engine. Affected version: ===== 0.6.12 Vulnerability Description: ========================== 1. the cr_tknzr_parse_comment function in cr-tknzr.c in libcroco 0.6.12 can cause a denial of service (memory allocation error) via a crafted CSS file. ./csslint-0.6 --dump-location libcroco_0_6_12_memory_allocation_error.css ==21841==ERROR: AddressSanitizer failed to allocate 0x20002000 (536879104) bytes of LargeMmapAllocator: 12 ... ==21841==AddressSanitizer CHECK failed: /build/buildd/llvm-toolchain-3.4-3.4/projects/compiler-rt/lib/sanitizer_common/sanitizer_posix.cc:68 "(("unable to mmap" && 0)) != (0)" (0x0, 0x0) ... #10 0x7fd78c2fcb4d in cr_tknzr_parse_comment /home/a/Downloads/libcroco-0.6.12/src/cr-tknzr.c:462 #11 0x7fd78c2fcb4d in cr_tknzr_get_next_token /home/a/Downloads/libcroco-0.6.12/src/cr-tknzr.c:2218 #12 0x7fd78c356f6e in cr_parser_try_to_skip_spaces_and_comments /home/a/Downloads/libcroco-0.6.12/src/cr-parser.c:634 #13 0x7fd78c368a43 in cr_parser_parse_stylesheet /home/a/Downloads/libcroco-0.6.12/src/cr-parser.c:2538 #14 0x7fd78c368a43 in cr_parser_parse /home/a/Downloads/libcroco-0.6.12/src/cr-parser.c:4381 #15 0x480a8e in sac_parse_and_display_locations /home/a/Downloads/libcroco-0.6.12/csslint/csslint.c:960 #16 0x480a8e in main /home/a/Downloads/libcroco-0.6.12/csslint/csslint.c:1001 #17 0x7fd78b397f44 (/lib/x86_64-linux-gnu/libc.so.6+0x21f44) #18 0x47c95c in _start (/home/a/Downloads/libcroco-0.6.12/csslint/.libs/lt-csslint-0.6+0x47c95c) Reproducer: libcroco_0_6_12_memory_allocation_error.css CVE: CVE-2017-8834 2. The cr_parser_parse_selector_core function in cr-parser.c in libcroco 0.6.12 can cause a denial of service(infinite loop and CPU consumption) via a crafted CSS file. ./csslint-0.6 --dump-location libcroco_0_6_12_infinite_loop.css Reproducer: libcroco_0_6_12_infinite_loop.css CVE: CVE-2017-8871 =============================== qflb.wu () dbappsecurity com cn Proofs of Concept: https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/42147.zip |