Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2d1404cf90f2a01…

MALICIOUS

PDF

86.4 KB Created: 2021-06-29 11:09:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 944a173d1419b5b31efc1ad249517962 SHA-1: e4cd6c279acd46dab92c7234ecbb39fc8eb4c536 SHA-256: b2d1404cf90f2a01cdae6cbee22daa4da5cf07e9491fa48c4da6e11a4f48cb75
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites utilizing form plugins for file uploads. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but serving as a container for the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080dc1fc7431---9690111950.pdf
    • http://bebelino.ru/userfiles/file/48082907756.pdf
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/1cc4fd8f0f25e19bf4af5bd54b2d2942/nevibakiwozeduponawo.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/po7nt7674q9c1viuukum098dh9/94180767483.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608406690e815---mijikibanufonefil.pdf
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093ab1e74c3d---82109560860.pdf
    • http://remaining-mc.de/userfiles/file/fekuromifopofimafebe.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607375c4b39b8---rawotanopolamogile.pdf
    • http://drive4smilesquebec.ca/clients/f/f5/f58105ca183540932673f5bf18e62671/File/fatovisujasuvitevew.pdf
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607051d7aa63b---kalusanalukakejejesu.pdf
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/jmobi7gmoll0nejhr9ql9ocgo0/delomurovowu.pdf
    • https://sinarwaja.com/account/files/19955353370.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f209ce1ed9---mizaxujapamesavogiregesul.pdf
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/1d2c5ac7b64856ba0f851f6b625868a9/tejejufarevanem.pdf
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/09k2jh21eg5utm4gpd0m6vqf96/depuxomubut.pdf
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/3974476d617c10a647670f2ed44d698e/dofepuxob.pdf
    • http://mobydick-band.de/fckdata/file/koreradugejofonesox.pdf
    • https://dpmceramiche.it/file/72538031313.pdf
    • http://bioscipublisher.com/files/upfiles/file/vanejesadiroladiroveje.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16092d58f4276d---gudekaredujufuwopuwa.pdf
    • https://artlabjo.com/userfiles/file/8517612305.pdf
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/b1798c902589446efad5b6fe7d135546/dubufewigemobidimezuza.pdf
    • http://adance0112.com/upfile/editor/file/nokagab.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=land+for+sale+with+natural+spring+water
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/6f62735666f03f2a323c6f67d919bbfb/32015778767.pdf
    • 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_off0000ebe3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBE3 16792 bytes
font_01_sfnt_off000103fa.bin
76e318fa78dc434d5382a0b5d0657b9621e8f75dc01ad2237992158ca0242acc
pdf-font-stream PDF embedded font (sfnt) at offset 0x103FA 10920 bytes
font_02_sfnt_off00011d03.bin
cda03e695233f9438d80dc4d5dce35481bfb861ed1621e4678445567f9419ccd
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D03 17588 bytes