Malicious PDF — malware analysis report

Static analysis result for SHA-256 90f8f5111b3f4dfb…

MALICIOUS

PDF

73.2 KB Created: 2021-09-01 07:57:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c473ffddc2e305dfdc2a92edcd2230c1 SHA-1: 8f934921a3e8318595bd059bd675c1ee7b0d10f2 SHA-256: 90f8f5111b3f4dfb318ed0170a6346b6144654451ad6bd999367aa6a9068ebcf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to multiple websites hosted on compromised WordPress installations, identified by the 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristic. The ML classifier and ClamAV also flagged this file as malicious, indicating a high likelihood of phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the numerous external links are the primary indicators of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://ever-pioneer.com/upload/files/dagavemud.pdf In PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/6em52pj8tg728ovmv7mavtosl0/53038610966.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/90d8050dc125d9bc60e5c821494ef649/kifedu.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608f7525e435b---rowofifutifeje.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/65ec230f98f9af49609ad3d72f1fbd23/42111180380.pdfIn PDF document text
    • http://stevis.cz/files/file/74575472218.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/31b567a22e35c94cfb15729e89a87d16/11405554314.pdfIn PDF document text
    • https://kalyna.ua/sites/default/files/userfiles/file/60894524606.pdfIn PDF document text
    • http://mywayrtk.info/userfiles/file/74833243367.pdfIn PDF document text
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/n60csk8l87ftej8tvh0u84iq9r/zewatelesunepixosurevon.pdfIn PDF document text
    • http://aybar-gallery.com/userfiles/files/mejusudarix.pdfIn PDF document text
    • https://talenthunt.biz/userfiles/file/88927900.pdfIn PDF document text
    • http://ekolojikweb.net/upld/userfiles/file/39919128643.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/h7c9484h69vvsel4f5iou5ke54/wosidemadewexar.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/pokjh7cuqua3v85t17k94ksf4r/21916235042.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609cea2702b3f---45999169549.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/16070af31eb21c---lewebadakopivopujozudato.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/60c63f28ff23272491defa4d45cbcc9f/86569941489.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3244ae4a73---12480072630.pdfIn PDF document text
    • http://twozonechickenlasvegas.com/uploads/files/98689165189.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/39516279396.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/1bcb6ea765f8d0e5c06518b48a204568/76665442935.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160c0ca607030a---boluwe.pdfIn PDF document text
    • http://www.prieteniitehnicii.ro/documente/file/38790428533.pdfIn PDF document text
    • https://bczenekar.hu/files/file/lakimaburuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=the+prodigal+son+1981PDF 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_off0000bb84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB84 10964 bytes
SHA-256: df51f4559e3ddf7cdfbb3f611062eeba7403c79904157ce6cc488fac6952fc39
font_01_sfnt_off0000d4ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4AB 16104 bytes
SHA-256: e91fff9b2a0606e5be640fdbc7b2ac967bac4d46d31afd5fb6f05a3454872232
font_02_sfnt_off0000fcbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1