pcre2test.c in PCRE2 10.23 allows remote attackers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact via a crafted regular expression.

PCRE2 before 10.30 has an out-of-bounds write caused by a stack-based buffer overflow in pcre2_match.c, related to a "pattern with very many captures."

Buffer overflow in PCRE before 7.6 allows remote attackers to execute arbitrary code via a regular expression containing a character class with a large number of characters with Unicode code points greater than 255.

The compile_branch function in pcre_compile.c in PCRE 8.x before 8.39 and pcre2_compile.c in PCRE2 before 10.22 mishandles patterns containing an (*ACCEPT) substring in conjunction with nested parentheses, which allows remote attackers to execute arbitrary code or cause a denial of service (stack-based buffer overflow) via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror, aka ZDI-CAN-3542.

The pcre_compile2 function in pcre_compile.c in PCRE 8.38 mishandles the /((?:F?+(?:^(?(R)a+\"){99}-))(?J)(?'R'(?'R'<((?'RR'(?'R'\){97)?J)?J)(?'R'(?'R'\){99|(:(?|(?'R')(\k'R')|((?'R')))H'R'R)(H'R))))))/ pattern and related patterns with named subgroups, which allows remote attackers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

PCRE before 8.38 mishandles (?123) subroutine calls and related subroutine calls, which allows remote attackers to cause a denial of service (integer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

PCRE before 8.38 mishandles the [: and \\ substrings in character classes, which allows remote attackers to cause a denial of service (uninitialized memory read) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

The compile_regex function in pcre_compile.c in PCRE before 8.38 and pcre2_compile.c in PCRE2 before 10.2x mishandles the /(?J:(?|(:(?|(?'R')(\k'R')|((?'R')))H'Rk'Rf)|s(?'R'))))/ and /(?J:(?|(:(?|(?'R')(\z(?|(?'R')(\k'R')|((?'R')))k'R')|((?'R')))H'Ak'Rf)|s(?'R')))/ patterns, and related patterns with certain group references, which allows remote attackers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

PCRE before 8.38 mishandles certain repeated conditional groups, which allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

The pcre_exec function in pcre_exec.c in PCRE before 8.38 mishandles a // pattern with a \01 string, which allows remote attackers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

PCRE before 8.38 mishandles the /(?:|a|){100}x/ pattern and related patterns, which allows remote attackers to cause a denial of service (infinite recursion) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

PCRE before 8.38 mishandles certain instances of the (?| substring, which allows remote attackers to cause a denial of service (unintended recursion and buffer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror, a related issue to CVE-2015-8384 and CVE-2015-8395.

PCRE before 8.38 mishandles the /(?|(\k'Pm')|(?'Pm'))/ pattern and related patterns with certain forward references, which allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

PCRE before 8.38 mishandles the /(?J)(?'d'(?'d'\g{d}))/ pattern and related patterns with certain recursive back references, which allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror, a related issue to CVE-2015-8392 and CVE-2015-8395.

PCRE before 8.38 mishandles the interaction of lookbehind assertions and mutually recursive subpatterns, which allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

PCRE before 8.38 mishandles the (?(<digits>) and (?(R<digits>) conditions, which allows remote attackers to cause a denial of service (integer overflow) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

PCRE before 8.36 mishandles the /((?(R)a|(?1)))+/ pattern and related patterns with certain recursion, which allows remote attackers to cause a denial of service (segmentation fault) or possibly have unspecified other impact via a crafted regular expression, as demonstrated by a JavaScript RegExp object encountered by Konqueror.

pcre_jit_compile.c in PCRE 8.35 does not properly use table jumps to optimize nested alternatives, which allows remote attackers to cause a denial of service (stack memory corruption) or possibly have unspecified other impact via a crafted string, as demonstrated by packets encountered by Suricata during use of a regular expression in an Emerging Threats Open ruleset.

Heap-based buffer overflow in pcre_compile.c in the Perl-Compatible Regular Expression (PCRE) library 7.7 allows context-dependent attackers to cause a denial of service (crash) or possibly execute arbitrary code via a regular expression that begins with an option and contains multiple branches.

Multiple integer overflows in Perl-Compatible Regular Expression (PCRE) library before 7.3 allow context-dependent attackers to cause a denial of service (crash) or execute arbitrary code via unspecified escape (backslash) sequences.