Malicious PDF — malware analysis report

Static analysis result for SHA-256 03cef56b8665b8d9…

MALICIOUS

PDF

95.4 KB Created: 2021-06-28 04:34:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7b09ab90b09ec1809257485f9d419876 SHA-1: dd4bd5286079e7ecee10f171b0203313883f0bfe SHA-256: 03cef56b8665b8d95460ea611fcc57647d1974db7bd8c1123cbe026663d9dee2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm directing users to multiple external URLs, with several pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, preventing a more detailed analysis of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://chalappuram.com/userfiles/file/14934365014.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6035d2cc6---lunubikubavowerewogepal.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/tsdnpjbssn7tfokuiudpsoascm/winusikudod.pdf
    • http://jevades.com/aircraft/fckimages/file/44208430449.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb0c86b65d---80161876425.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/3661fd5445b3d1a51527af538137d521/85603739408.pdf
    • http://erdivigado.hu/userkepek/file/62627795499.pdf
    • http://czdashan.cn/uploadfile/file/2021051401474773499.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608e910f37d7b---vekibera.pdf
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/0aa47187f0b4690a3723f3de1e5006e3/3514999944.pdf
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/1b184c5cf11cc3d2a04c6a8df4ae6c73/jofuxopesi.pdf
    • http://ttmplus.com/userfiles/files/raviz.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/d31b7d904ad38a37e197660da0e95c48/1465800598.pdf
    • https://506hlapeta.com/files/file/18208130466.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d34f05fbb---tolofepuradigoz.pdf
    • http://master-sign.ru/ckfinder/userfiles/files/jipupigobizirivisita.pdf
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ffb31a0bc6---bafakuvaxoda.pdf
    • http://beateromer.com/bilder/file/bepikezegukategeg.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b482fd6c49d---29376399861.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7815448146---62440978034.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/734d0c002711762a7a8ab2cb50ac5ef3/sivikul.pdf
    • http://alkanboya.com/files/file///sobugukodukefojeb.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608703790b2fc---vetilepevewonotom.pdf
    • http://sukhabalka.com/files/file/23127222859.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=mainframe+db2+interview+questions+and+answers
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010f8c.bin
fbb89f52d6edc2c829b8eb6c33ade0404da17b311566d31f4313a03617cfb24b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F8C 17792 bytes
font_01_sfnt_off00013e37.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E37 16792 bytes
font_02_sfnt_off0001564e.bin
967600b5f083b538f411d899bd188d0d854e6137bd787ba50130c1ba09884c76
pdf-font-stream PDF embedded font (sfnt) at offset 0x1564E 11120 bytes