Malicious PDF — malware analysis report

Static analysis result for SHA-256 8285e1bc6abb5787…

MALICIOUS

PDF

92.4 KB Created: 2021-08-30 14:02:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5f1b77e2e62d367ee659c93a02d94348 SHA-1: 97aa09a9c24408b599fafdc9d138e125b06ca9fc SHA-256: 8285e1bc6abb578724e428678af7efdb5cede89757a454201a92aed8ff0a55b3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload locations and disposable hosting sites. The embedded URLs, such as 'https://crewmak.ru/uplcv?utm_term=an+amount+of+money', likely serve as lures for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://crewmak.ru/uplcv?utm_term=an+amount+of+money PDF link annotation
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16129ed39daf89---wimubevazikubakomuvebeza.pdfIn PDF document text
    • https://stiff.pl/ckfinder/userfiles/files/2913241936.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/bewub.pdfIn PDF document text
    • http://faulkfamilync.com/clients/c/cc/ccb94402b1eed20a0583117be0c0b506/File/ratisabivazali.pdfIn PDF document text
    • https://pensiuneavlasin.ro/wp-content/plugins/super-forms/uploads/php/files/oin5gc9hhronljr7aou6hdoq8n/21702219606.pdfIn PDF document text
    • http://omgmediatank.com/userfiles/files/40090958553.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1611bc34c6c957---35353730262.pdfIn PDF document text
    • https://mangalargalux.com.br/ckfinder/userfiles/files/mesivariwunafopukinowoda.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609156347bd6c---40086861152.pdfIn PDF document text
    • http://mayinluatudong.com/uploads/userfiles/file/fajexajivudenomafoneg.pdfIn PDF document text
    • http://compow.net/ckfinder/userfiles/files/vemunoxitoborakizonapon.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075510f067b9---nisakujogesowixaxar.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/d0152d6a9f734aa4fa08419a9a2157b3/dokabanoruzimelokuv.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16102f7142c605---76469637706.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/pnth0ru3d4lvd463md3ggkf294/66949851574.pdfIn PDF document text
    • http://rh-h1tapi-turbo.com/contents//files/70550793181.pdfIn PDF document text
    • https://nexusmediation.nl/files/46488051370.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607f38fb60b6b---tejufebixiw.pdfIn PDF document text
    • http://mingmitrcoffee.com/user_img/files/13903777311.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/21684873343.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/1tubaua725j4j5c6js1dpf673f/pirurabefafegeruvijiv.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/c4vlr9r4iivef6dfqdijh1bbev/nifevikin.pdfIn PDF document text
    • http://lookkorea.net/userfiles/file/durotegunodob.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0850e5727e---lodebajulileludise.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/1ceb4e663cea93b563d1f08c57ac04dc/54499800289.pdfIn PDF document text
    • 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_off00010534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10534 10164 bytes
SHA-256: d2c2536871155f4f816bfc3e3a0b16dc0bac503f67ff2598b8d0b28d544446d3
font_01_sfnt_off00011c08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001341a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1341A 18484 bytes
SHA-256: 193a02b264c9ba803821f03226497a890ea9b60ca3fc4b35bebca884e34677a3