Malicious PDF — malware analysis report

Static analysis result for SHA-256 a12b53f5983a0e86…

MALICIOUS

PDF

85.2 KB Created: 2021-06-26 05:08:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 216b07412edc41f2715114bec3a5b65e SHA-1: e38982910ab0a03976f06e04b175c39cd8aef1d8 SHA-256: a12b53f5983a0e86d3c3043e3c7f67077aec60f4bc0a2792505ec21876ae45b7
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories and other potentially malicious sites, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://sillajen.com/fckeditor/_upload/file/mizuxaw.pdf In PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/4a68757245c306409ef05f206c417fe8/64040589067.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/84kbusdnq5185ctiilnrfpfn94/vitafabapasubojoxiboz.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/2koihvmq9dt7lueihh2f7gkrq8/pezatijoluwe.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/rinubafafawosud.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160835de58e157---28265599878.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/a38v75ebkfoclpv0mm8tnhl341/74791890202.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/nl99qre8aboi3evarncr9q9dpe/vunideniwafokob.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/gelawubewusosuvimezelijox.pdfIn PDF document text
    • https://tonwen.org/userfiles/file/rizisumixukoluzuj.pdfIn PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/c8e7b4c93165de3dba464ade0f16dcdf/nivizidisapupikos.pdfIn PDF document text
    • http://warraichmeats.com/wp-content/plugins/formcraft/file-upload/server/content/files/160898e108fc5b---xepozekudanifufodiwowud.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9204dd4c8b---69981592959.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/35433918526.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/94ed682d5abcd7bac650c204505bf08d/27848039688.pdfIn PDF document text
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/pep3l3qjn40tshk54dtl7fov2s/vimowivipowalom.pdfIn PDF document text
    • https://ambient-interier.cz/files/files/kasojimawezivijekamuxasen.pdfIn PDF document text
    • https://sukhayurveda.in/userfiles/file/nitisoxokomaxuzo.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/36e4cc2dc762ce106db9ff7ed5fc1404/26773514239.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160741c89bf831---15230682436.pdfIn PDF document text
    • http://bigxra.com/uploadfile/file/2021061516124073499.pdfIn PDF document text
    • https://medtek.vn/storage/file/59056450177.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/be3975b5738cd40bd84f8b2cd94f278f/liser.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607638cf32de9---5370835076.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607f25e077ea0---22715677795.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/u30iqpvd79cfs7dgss7np28718/vusubowafaxowe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=average+cost+and+marginal+costPDF 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_off0000eb35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB35 10760 bytes
SHA-256: 79456604fc383a5fff89ae3985f7e1075194b89ab4c11a18276ebd37591e8eb7
font_01_sfnt_off000103c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C0 16688 bytes
SHA-256: 4d96f6d62da9930504fac5a6b7e071a0e8bf0d3b4b890ac45e9adec7502c877f
font_02_sfnt_off00012f4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1