Malicious PDF — malware analysis report

Static analysis result for SHA-256 27dc79b8cd2f4c0c…

MALICIOUS

PDF

82.8 KB Created: 2021-08-15 22:15:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 111f86c1e4706d47c80e34818e8b14d0 SHA-1: 65c801251bb44d60d60780f495e77c3e09ffa602 SHA-256: 27dc79b8cd2f4c0c208c8b2f27d49b2fa5e0bbb60e17f6e22c3661e257180a42
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 sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirm the link farm nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/b8i167rkrb0b4mmqhaeo7fd3r1/80930752947.pdf
    • https://kingdom.vn/userfiles/file/wakixubapedolagifi.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16080e82703f8c---69203858210.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160f15aa5c69db---13855695340.pdf
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7dc1c0832---kedimagesosuwuziwofuvu.pdf
    • https://arerp.kr/data/file///7481798427.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6e46b816b---dasisipazubevanawito.pdf
    • https://isleo.com/i_photos/file/9456945808.pdf
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b325998efe9---gojimaxogu.pdf
    • https://hoakhanh.vn/uploads/image/files/12361650231.pdf
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fac632f686---naxijifademirifewuko.pdf
    • https://ryokanclub.com/FileData/ckfinder/files/20210705_CBD2AA93B3EC29BC.pdf
    • http://interface-referencement.com/userfiles/file/71902268992.pdf
    • http://iccarrentals.com/files/file/72470916831.pdf
    • http://fritz-fahrlaender.ch/download/56087339302.pdf
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/072c0ad63820da3a0085a7add425dd34/rikodukiz.pdf
    • http://autosklo.sk/pictures/file/numitadedilogepixit.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bafebf8f647---94364287460.pdf
    • http://midel.me/userfiles/file/sikememepumolaze.pdf
    • https://coil.hk/upload/files/76515605692.pdf
    • http://extracam.es/app/webroot/arxius/file/xenafebunulipabujosudev.pdf
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160870323d7490---wuloluweroraripafiminumi.pdf
    • https://whitesal.com/data/images/file/5524_20210713045032.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+measure+miter+cuts+for+crown+molding
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e04b.bin
e28d5c7bc407c62481c6707de7f4fc67a83ecdd914ac799eb338f28c24161bb9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE04B 10996 bytes
font_01_sfnt_off0000f9a1.bin
5ca076ed6217aa50e0dd043edd9e8d55880bfe047b50aa0019656842815c2757
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A1 16728 bytes
font_02_sfnt_off00012518.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12518 16792 bytes