Malicious PDF — malware analysis report

Static analysis result for SHA-256 2862b72ec53a2bf7…

MALICIOUS

PDF

88.1 KB Created: 2021-08-08 07:59:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2f8b367af22125a473841b8980cd2a84 SHA-1: 11d0e79d27e556736d6e01cc406e120d167e5b0c SHA-256: 2862b72ec53a2bf7e02c65d4e6f2456753a526472a811ea0a3c6f1b5c415d402
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, flagging it as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories or are part of a link farm hosted on disposable domains. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user consumption but rather as a vehicle for hosting these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://kzlo.pl/fotki/fotki/file/joxizejovivijimenivu.pdf In PDF document text
    • http://zonweringbelgie.eu/ckfinder/userfiles/files/44426969429.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1610ce06b17802---31052405839.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/danim.pdfIn PDF document text
    • http://studioschicchi.eu/userfiles/files/silesatafam.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160841eb16494c---peviboxaxolalonobamuvivu.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160be4cadcc033---levafigewesojavume.pdfIn PDF document text
    • https://pasarantogel.com/contents//files/peteletosarupujawopoto.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/29450723135.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/78360195923.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/4429ed3454f991ecb9f859337ba0eaa6/toreposabe.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094b86fcde4e---visoli.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093d120199da---kejorabotugemekivoduzi.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160962a06aad6b---lipubekepafetuwub.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088368287f0c---95615527671.pdfIn PDF document text
    • http://wienbildarchiv.com/upload_files/files/vevedijajufujoboduzatus.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/vubufalebeguguzemake.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/6e7986926019c0b00baf178f71a1b067/xuxikav.pdfIn PDF document text
    • https://astdubai.co/userfiles/files/tazokojot.pdfIn PDF document text
    • https://shellserva.nl/docs/Image/file/5596773110.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8fa1abf94b---mefobova.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/zusenexelagemem.pdfIn PDF document text
    • http://arebiatours.com/uploads/files/subinewigimizogufuveto.pdfIn PDF document text
    • http://kamerton.nl/clientfiles/9961126103.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=how+much+do+you+feed+a+baby+corn+snakePDF 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_off0000f6bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BB 11028 bytes
SHA-256: 37593916f253425066c8ad39e35f22b287530e444b6911156a3cdd7af00472d1
font_01_sfnt_off00011038.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11038 16452 bytes
SHA-256: 38dc8205aa70a67b7d60d68c5eb51c3650fbc5fe3a4c2ec5af30cc171a29242e
font_02_sfnt_off00013add.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13ADD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1