Malicious PDF — malware analysis report

Static analysis result for SHA-256 a57bd5d4c82a6a5a…

MALICIOUS

PDF

96.3 KB Created: 2021-07-22 21:16:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 57bb09bf686a6d1ffdfba8edd9c28971 SHA-1: e9b8d11a9f46e9dc1d28990260f5e1e9cc20eb09 SHA-256: a57bd5d4c82a6a5a9fa35f60e52e51d559359db45848d425ba979eec088d874c
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of multiple unknown URLs further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160f0a84781eef---81556927035.pdf In PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/bb4456e9a4d7b7f5412e1bc481e4dda6/17802195286.pdfIn PDF document text
    • https://www.ojchamber.com/ckfinder/userfiles/files/puletokuxoje.pdfIn PDF document text
    • http://diysmart.net/userfiles/file/62864864149.pdfIn PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba0b0c90797---vabuj.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/06a7130ade3b5c6cc97c26120d23b129/golozaz.pdfIn PDF document text
    • https://sanidom.pl/img/file/watabetabudofavobikesosej.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f121b3132d---kosogumafewotonogabebula.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/63059733944.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/59c760b5tqjjkgfc5q2sl1o1pl/81830442786.pdfIn PDF document text
    • http://brianhaymore.com/images/e/file/labutoremasupof.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cee55c95061---zidopepu.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///47005399474.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/uv9tl05u50ciqgs0109i2fdj5u/kiwasogufujapijuniw.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/xiruturifanakudew.pdfIn PDF document text
    • http://rmgoals.com/userfiles/files/rufojikegoperobebaxidok.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b244d2dd319---61253670010.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c418aba3cde---40630804055.pdfIn PDF document text
    • http://vetcasatenovo.it/userfiles/files/43190812407.pdfIn PDF document text
    • http://bajajsports.com/userfiles/file/nilupusubawafesobipi.pdfIn PDF document text
    • http://bernardthevenet.fr/ckfinder/userfiles/files/16788388713.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/94c89f9c0785e13338894b0110213e10/39360575289.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16077ec85483b3---bofaguwedugosalupig.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/togedumutupuweju.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/2d1acdd14149bd6a52840f33049a788f/pebepogulur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=zombie+attack+ps2PDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000114e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114E4 17820 bytes
SHA-256: 10c0fcdec441f6139ba9db52ab5ac3a51cf265550121cb4986c9c497434bc87a
font_01_sfnt_off0001434a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1434A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015b61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B61 10600 bytes
SHA-256: 205ef8a492f76e623fc5b650dafd537bc0609eecdc407c85e9adb7e5c6047647