Malicious PDF — malware analysis report

Static analysis result for SHA-256 94d241cda8b88fe0…

MALICIOUS

PDF

85.6 KB Created: 2021-08-03 10:05:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0b298e1debbf632d0ba0b95fa8a580f4 SHA-1: cd0ad6e64782b78d8359c5bc56a333e4975ac7fa SHA-256: 94d241cda8b88fe0d0d71126768c6caf758e315b5760c22206fe0e35e8457001
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting it's used to redirect users to malicious sites. The embedded URLs are likely part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://bayanairag.com/uploads/userfiles/files/97673261654.pdf
    • http://desushibar.com/userfiles/file/kozufebu.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608d661ba681e---30370176151.pdf
    • http://tweedehandswikkelaar.nl/app/webroot/files/userfiles/files/vajukidudaxu.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c757fae40d7---71878341120.pdf
    • https://www.westcountrystoves.co.uk/wp-content/plugins/super-forms/uploads/php/files/9100ecda781a4870b321397a548c6525/64225177748.pdf
    • https://techielingo.com/fck_uploads/files/29985236370.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a51a56b42fa---24809912715.pdf
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/s0rraglf9pr8n7se95t9pmgdq9/43760073020.pdf
    • https://cornwallstaffagency.com/userfiles/file/zurudanuvozo.pdf
    • http://unipsyclinic.com/userfiles/file/20210619204859.pdf
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/cdc018609f66430aa0989aebc5d2c865/58388468828.pdf
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/673aed73e81b56aba1df9056ec14a0c0/48168460097.pdf
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160e4c6378f8b8---telogumavilakorokimawog.pdf
    • http://mp-journal.com/media/file/53335823612.pdf
    • http://clinicaveterinariailmarzocco.it/userfiles/files/jutozuvalodetadarasiv.pdf
    • https://mmszke.hu/files/file/negiresub.pdf
    • https://tessuno.com/upload/files/60f71b5db19ac.pdf
    • http://celcg.pl/uploaded/file/potisi.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/252a2e0e49d2c494a05f63440359fc7e/51894662432.pdf
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/baad6cf7a6738f7fe835b665e5aea7ce/60283840208.pdf
    • https://avela.md/userfiles/file/4253153449.pdf
    • https://protrialse.eu/files/files/18120160335.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=lengua+y+literatura+1+bachillerato+temario
    • 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_off0000e672.bin
e0b6a6b4f3ad7ea730c05a7ed3a5529fea6f1bf8c952873afb6671c677162133
pdf-font-stream PDF embedded font (sfnt) at offset 0xE672 10872 bytes
font_01_sfnt_off0000ff6c.bin
34297c31ce8262c52ee08b12ea0c0a98e37ca16239982d4f542ae6bc5683578f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF6C 18988 bytes
font_02_sfnt_off00012ec6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EC6 16792 bytes