Malicious PDF — malware analysis report

Static analysis result for SHA-256 653bd4250ff492e9…

MALICIOUS

PDF

80.9 KB Created: 2021-09-06 21:31:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: d58a50359395eb934477e84bc43d8df1 SHA-1: d3597a82c908bbb12044a357e4543ef4190aaac9 SHA-256: 653bd4250ff492e98265a21322fe1d58e2098a5c23611719aea5c327030600bf
156 Risk Score

Malware Insights

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

The PDF was identified as malicious by a machine learning classifier and ClamAV, with heuristics indicating it functions as a link farm. Many of the extracted URLs point to compromised WordPress sites, suggesting an attempt to lure users to malicious content or phishing pages. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific intent beyond the link farm behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/43875643082.pdf In PDF document text
    • http://appartenvue.net/appart/upload/images/82394142198.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/memefuzilejebi.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160889381d12e8---9781470179.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/parigotawidozurazuvowapat.pdfIn PDF document text
    • http://beijingxinzhi.com/userfiles/file/20210625064912_642779129.pdfIn PDF document text
    • http://kdbelektrotechniek.nl/uploads/file/99969131321.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/622269465c7a9520ff5d2f59b8087c83/kidok.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c851466f622---fatezuw.pdfIn PDF document text
    • http://truhlarstvisollner.cz/data/file/zefuwu.pdfIn PDF document text
    • http://mrmax.ca/clients/9797/File/wisafe.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/nlqindncu68ukcdgktrtand41q/busajidutosivefifole.pdfIn PDF document text
    • http://xn--80adic7alej3d.xn--p1ai/userfiles/file/42252999543.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/rewenisozem.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/841a8e345de1ff7ac1697cd2c01fe9b2/luxenawarevolasidir.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/6vp4eq3l29bece29qfj5i3fln7/wavarofazagofevijifusana.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce378a803a9---gafat.pdfIn PDF document text
    • http://tuclubcr.com/campannas/file/26755800283.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612a84a1311a4---76399218000.pdfIn PDF document text
    • https://www.colours-of.com/wp-content/plugins/super-forms/uploads/php/files/a3dhlaue1figgtm0ik48h2c2tj/dibijurafekeda.pdfIn PDF document text
    • http://kup-vino.cz/web/ckfinder/userfiles/files/nekomikokifa.pdfIn PDF document text
    • https://foursservices.com/nbloom/fckuploads/file/ruzefobetatus.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/13e64b342a23d5bab7d7193bf938b8c0/xevopiler.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=engineering+measurement+tools+pdfPDF 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_off0000d7ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7EE 17460 bytes
SHA-256: 016532389f489553a9fd01060866dab87567270b18cd21b0f4f90392d0e3c22a
font_01_sfnt_off0001051f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1051F 10924 bytes
SHA-256: a6a17eb60437e730b3ac5bd8120fa1802fda4bc9e399586aa6d6c976d3a25437
font_02_sfnt_off00011e2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1