Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d10d194a351b185…

MALICIOUS

PDF

113.3 KB Created: 2021-07-04 02:35:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 28dfd46fafbc2a10c5ce889741212e68 SHA-1: bfd59fc79013f676b6cc2edaed0451eae7d931db SHA-256: 3d10d194a351b18566d8042d9464284d4b264dd261378cb013d5f97445ad6b1a
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. The presence of multiple distinct hosts and disposable hosting further supports this. The document body is heavily obfuscated and unreadable, providing no direct textual clues, but the heuristic findings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

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 https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ae57680f164---fewokisegilej.pdf
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/1vepltd9h3u7mtnnc88oe2lca5/2015014641.pdf
    • https://travelstore.tn/userfiles/file/ridefepuzidexi.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/804752401d734bbac572a1ec0056ecfa/67046968176.pdf
    • http://ipmarketing.net/userfiles/file/18780108743.pdf
    • http://thesprotia.gr/uploads/file/jelubuturisabododatoxemu.pdf
    • http://kalmi.ru/upfiles/files/jipadufelopa.pdf
    • https://easypayindia.in/userfiles/file/63238065568.pdf
    • https://aartipalette.com/userfiles/file/varapudadopofumu.pdf
    • http://www.aportecnica.com/imagenes/editor/file/68304607423.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160893e3eb9057---xezezuj.pdf
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6b082a2ff---13341419123.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ce0017d398---donekepegupete.pdf
    • https://careersourceokaloosawalton.com/files/public/54075449589.pdf
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160882a73834a5---58617665915.pdf
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/651e03006a610666d87198855db23a6c/60072339845.pdf
    • http://chrislahoda.ca/userfiles/file/zikitogaze.pdf
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/ee9a8559063939cd24ca8dc87466d9f3/69384853210.pdf
    • https://carparts-fixture.com/file/file/nabiwivatofekamibegipoziv.pdf
    • https://dolmalatrek.com/userfiles/file/606429475.pdf
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/b6ea8ad3067010d888162be6dbaab79f/37948592400.pdf
    • http://aiswaryamatrimonials.com/fck_uploads/file/tidegazilevidezerureki.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=two+stringed+fiddle
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011bd0.bin
092b02ebfb17c3ea52495e0c00a0c195b08a6783c869dae05a51987792894643
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BD0 18904 bytes
font_01_sfnt_off00014bbf.bin
94ad7736e334f7e78b01527b3be371bba9ecc6970094934604a2d504ac1e2821
pdf-font-stream PDF embedded font (sfnt) at offset 0x14BBF 10416 bytes
font_02_sfnt_off00016349.bin
dc19bcc0cbcbb7a235efd32a9bd97342425fafb9f7a21b2c60112420df568bcc
pdf-font-stream PDF embedded font (sfnt) at offset 0x16349 21240 bytes
font_03_sfnt_off00019f7e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x19F7E 16792 bytes