Malicious PDF — malware analysis report

Static analysis result for SHA-256 d87bc48b9be5eb74…

MALICIOUS

PDF

83.0 KB Created: 2021-06-26 09:37:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 4a602e2b438943ee9f2eb65510f5364c SHA-1: 8762b847125207ce102ed3580d5965563ec41ff8 SHA-256: d87bc48b9be5eb742ad3a7eeffca69811784167ad893caf1e3f6e0ff64ac3a96
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16084198a143e9---21060842100.pdf In PDF document text
    • http://rayzerfamilyreunion.com/clients/0/08/08e2d5bcffca37c2e1a82d364f4296c6/File/wanawasitomapevarexuved.pdfIn PDF document text
    • http://arebiatours.com/uploads/files/37846485244.pdfIn PDF document text
    • https://steklo-shik.ru/userfiles/file/wedawesazofozetedidiwemed.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/julipe.pdfIn PDF document text
    • http://candientushinko.com/images/file/fivilakelarepiruduw.pdfIn PDF document text
    • http://aiaato.com/FileData/ckfinder/files/20210619_F2393975F6CD1562.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/kasigotedezajuruxazava.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160736697b499c---30824526045.pdfIn PDF document text
    • http://amandamaitland.com/images/file/86846019954.pdfIn PDF document text
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/b99a2577d19f2dfa6ffced668a415143/48555049099.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/3ike4ifq0sp659tspomgqsl2r6/7392796678.pdfIn PDF document text
    • http://n-production.com/upload/fckeditor/file/25935821226.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16083b9c997533---5589753841.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/difujuxodoga.pdfIn PDF document text
    • http://flexicourse.cz/res/file/narinilol.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd2bec7c187---fijilalekopo.pdfIn PDF document text
    • https://weilaimachinery.com/userfiles/files/15860424212.pdfIn PDF document text
    • http://wtmongolia.com/materials/file/99811637211.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1d8508606---dulosasufepuwok.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ace7261476d---1550276677.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8d99a9b9a6---nefutumagilafegututunojez.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608242c51c65f---45484290069.pdfIn PDF document text
    • http://location-appartement-venise.com/italie_documents/files/derekomubodazuxutojew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=prince+william+county+assessor+property+searchPDF 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_off0000e41e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE41E 10940 bytes
SHA-256: 8f576bce6a3935f3d1ddf0ec2fcf8cfc0d7d32b976f51b925ea58df8af994952
font_01_sfnt_off0000fd5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5D 16020 bytes
SHA-256: 018ca389a153283323c66cf1b1016a5e255512ed70217a45b990e5bf31d2a448
font_02_sfnt_off0001269c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1269C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1