Malicious PDF — malware analysis report

Static analysis result for SHA-256 426bed37dcd1d35b…

MALICIOUS

PDF

85.2 KB Created: 2021-07-07 02:18:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2e61fa7b803ab161229fb4828d1292d6 SHA-1: 4313334d32e1d39513a9e09264ac616c88d3f5a3 SHA-256: 426bed37dcd1d35b1db8c3a111109db2348e6a45940b9a350fab8065a6a06305
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and disposable domains. These links likely serve as lures for phishing attacks or to distribute further malware. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://archism.ru/uplcv?utm_term=ddo+hall+of+the+mark+answers
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/160705bd9c1c8a---piwekemuwiwekemijapi.pdf
    • http://fygl.net/uploads/file/090853192539.pdf
    • https://susta.vn/userfiles/file/65895797858.pdf
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/e61a0e5a067d313875a7f74c92bfa457/sedifatalaziw.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/4rbbiu0ohtvnl40fee9j9rf2f6/mejubajajukemeg.pdf
    • http://sxhk365.com/uploads/file///zifokevokakopev.pdf
    • https://virtualpulse.eu/UserFiles/file/67731905474.pdf
    • http://wannawwannie.pl/userfiles/file/41656429885.pdf
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/8c73d315a6ac5103abf562eea6f60e05/43909949596.pdf
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/4fvre9itpbi24jvpnbmcmkflad/sinemovejiwejumimigexow.pdf
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a741e78fb31---78893266175.pdf
    • http://e-hematologica.pl/users//file/gosedejepekoxelis.pdf
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/2d8e8648abb5c6d7126106bc9bc8ef86/87102917560.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/b86f4a58eec255253734bfedf2a40fb2/furapetuwuxuzageziza.pdf
    • http://www.annaleehuber.com/content_files/file/puguvagidote.pdf
    • http://donateagift.eu/userfiles/file/dadobufogebunemobujezol.pdf
    • http://premium-t.info/files/files/67755604317.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608344f19f3ce---vejudurubavapimapipaxa.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607e822dc934d---xerikunuguwamuvusego.pdf
    • http://mg001.cn/upload_fck/file/2021-5-11/20210511114938543641.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160986a828e515---zepopugosepe.pdf
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609779fed048b---69977630878.pdf
    • https://sogelec-eng.com/files/ckfinder/files/wizupifiv.pdf
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/drj0aptiqafbvogie23i9ikdi7/99689460234.pdf
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2b8595d65f---wufabosadukobotaparufawij.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_off0000e929.bin
5d684c7cce9b5544f22f3f43983806600bdfba0281946595c07aaa13155c0866
pdf-font-stream PDF embedded font (sfnt) at offset 0xE929 17536 bytes
font_01_sfnt_off00011736.bin
606c98b3460da5505d3bb2ac001f81d47a8bf956d0252c7d7e65182d61b2a8b0
pdf-font-stream PDF embedded font (sfnt) at offset 0x11736 10704 bytes
font_02_sfnt_off00012faf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12FAF 16792 bytes