Malicious PDF — malware analysis report

Static analysis result for SHA-256 6600438efd346909…

MALICIOUS

PDF

2.7 KB Created: 1405-01-01 Authoring application: 5621
MD5: edafaef63ccafd6deb8f50947f1f3fd7 SHA-1: 3aa456c18b8bc19277bba1ac2e95195d52eb5fbf SHA-256: 6600438efd3469093be28eb386803e3df5be84c5d5943a87d95a557a84e23fdc
648 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains embedded JavaScript that leverages multiple known vulnerabilities in Adobe Reader, including CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The script is designed to download and execute a second-stage payload from the URL http://zarplata.ax3.net/load.php?stat=Windows. The use of eval() and unescape() functions, along with the exploitation of specific Adobe Reader functions, strongly indicates a malicious exploit kit.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 15

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (matched in decompressed stream)
  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (matched in decompressed stream)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (matched in decompressed stream)
  • Pidief-style multi-CVE JavaScript dispatcher critical CVE likely PDF_PIDIEF_MULTI_CVE_DISPATCH
    A single JavaScript body branches on app.viewerVersion and invokes two or more of the canonical Reader sinks (Collab.collectEmailInfo, Collab.getIcon, util.printf with a field-width format string). This is the 2009-2010 Pidief.J multi-exploit landing template: a per-version dispatcher that fires the matching CVE chain for whichever Reader version opens the file.
  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • Multi-CVE Adobe Reader JavaScript exploit kit critical PDF_ADOBE_READER_MULTI_CVE_JS_KIT
    One recovered JavaScript stage contains multiple version-gated Adobe Reader exploit branches. This is stronger evidence than independent API keywords: the PDF is selecting old Reader vulnerabilities by viewer version and running heap-sprayed Acrobat JavaScript exploit paths.
  • ClamAV: Pdf.Exploit.Agent-36014 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36014
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • Generic recovered JavaScript exploit stage high PDF_GENERIC_STAGE_RECOVERY
    Bounded static stage recovery exposed hidden JavaScript through generic transforms such as null-byte collapse, percent decoding, marker replacement, arithmetic character codes, fromCharCode, numeric arrays, numeric-array minus-key decoders, alphabet-index arrays, /Producer half-difference metadata arrays, hex literals, marker-stripped Base64 literals, custom 6-bit XOR table decoders, or repeated-marker hex carriers. This rule is emitted only when the recovered stage contains exploit-like Acrobat JavaScript or shellcode markers.
  • PDF JavaScript shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF JavaScript shellcode contains a hardcoded http(s) URL stored as little-endian %uXXXX Unicode escapes. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • Suspicious extracted artifact medium EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://zarplata.ax3.net/load.php?stat=Windows

Extracted artifacts 12

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0013_001.js
d5eb8e12b824507b1714237ed24e00951ff3d1383c0d91876de4c77688e973d3
pdf-javascript-stream PDF /JS object 13 at offset 0x328 4796 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 10 eval/decoder/string-building token(s). Carved artifact contains 3 long hex-escaped blob(s).
generic_stage_recovery_000.js
ebd9cf603b86acf6cd6d2ee13ebf9f74c7256308c58bf04978a5735e65342f4d
deobfuscated-js generic stage recovery split-literal-normalize from JavaScript object 13 at offset 0x328 4776 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 10 eval/decoder/string-building token(s). Carved artifact contains 3 long hex-escaped blob(s).
generic_stage_recovery_001.js
6bd9444bf450f9488592b9e56776acf674871c12c6926a78acafaa69dc1ed9a1
deobfuscated-js generic stage recovery percent-decode from JavaScript object 13 at offset 0x328 3918 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).
generic_stage_recovery_002.js
4de8ddc9fefb0a729c3597bda5841e4b00966e9ce20711fc3c97d6d7008117ac
deobfuscated-js generic stage recovery split-literal-normalize from combined JavaScript objects at offset 0x9 4787 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 10 eval/decoder/string-building token(s). Carved artifact contains 3 long hex-escaped blob(s).
generic_stage_recovery_003.js
6ced40ce0f7fe54d8a7babf3576bd85c20005ddf9af0c9396e337f88b8acd29d
deobfuscated-js generic stage recovery percent-decode from combined JavaScript objects at offset 0x9 3929 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).
generic_stage_recovery_004.js
1928ddb68b70c5bd7d652b68cf208cc2256abf4ca59afb0aba5fa1fec8d53c33
deobfuscated-js generic stage recovery percent-decode from decompressed stream at 0x328 at offset 0x328 3684 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).
generic_stage_recovery_005.js
ebbd795589aff5f0d4a7f52486ed51ac0882398bfcc57cb2596cd29bfabc7477
deobfuscated-js generic stage recovery split-literal-normalize -> percent-decode from JavaScript object 13 at offset 0x328 3898 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).
generic_stage_recovery_006.js
3bcce75b7011b4035e18f1f2672fd0263cf07807ae7663028d4cd3554c9e2c89
deobfuscated-js generic stage recovery percent-decode -> percent-decode from JavaScript object 13 at offset 0x328 3914 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).
generic_stage_recovery_007.js
db711c78629c5876016dae20cf8007764cdce5faa71edfa39bbba2e352145bc6
deobfuscated-js generic stage recovery split-literal-normalize -> percent-decode from combined JavaScript objects at offset 0x9 3909 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).
generic_stage_recovery_008.js
23cf8fac47ec1c10bf82b7f4d8d545200696f788e6bcb27d8064a4a2e8f38890
deobfuscated-js generic stage recovery percent-decode -> percent-decode from combined JavaScript objects at offset 0x9 3925 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).
generic_stage_recovery_009.js
3ed70f26058168d715451d5fd5e1d858a3ba859b8956e0ff621a26da06a73c58
deobfuscated-js generic stage recovery split-literal-normalize -> percent-decode -> percent-decode from JavaScript object 13 at offset 0x328 3894 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).
generic_stage_recovery_010.js
c0680061565ed7a88efbd54553a9b39c5cc190b490c9fb234f27c6fe35dc59a0
deobfuscated-js generic stage recovery split-literal-normalize -> percent-decode -> percent-decode from combined JavaScript objects at offset 0x9 3905 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s).