Malicious PDF — malware analysis report

Static analysis result for SHA-256 5641e4917225ca9c…

MALICIOUS

PDF

83.1 KB Created: 2021-09-22 18:28:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 76d0dd1657ae5c1eec387c11d880c350 SHA-1: d09150ea38c0b6c93948374805a15412edc98937 SHA-256: 5641e4917225ca9c45182fab9ac19d95f0219393089f3df50c62aeea2ec124b6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious intent. It contains an embedded JavaScript stream and numerous external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The primary function appears to be redirecting users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://oniceh.ru/uplcv?utm_term=videoder+apk+for+android+11
    • https://chinatupai.com/web/js/ckfinder/userfiles/files/mikixakuvagij.pdf
    • https://gamepinleri.com/calisma2/files/uploads/76211508482.pdf
    • https://777mto.info/contents/files/95966193021.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613985f9265c1---sukujadalewokopagotimupib.pdf
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/80389948645.pdf
    • http://hainescentreasia.com/images/file/zewakipekadesixilos.pdf
    • https://onderdurdu.com/upload/ckfinder/files/95377200392.pdf
    • http://chothuexeninhbinh.net/data/dulieu/files/76363934539.pdf
    • http://liebherr-tr.com/userfiles/file/82230327382.pdf
    • http://baugeraeteverleih.de/benutzerdateien/xukave.pdf
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/44035520392.pdf
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613519e94bdb9---82911903042.pdf
    • http://ocean-ex.com/images/blog/file/24196826195.pdf
    • http://open.ua/uploads/ckeditor/files/14718643475.pdf
    • http://modnyi-buket.ru/uploads/files/wokifugimejexamonakepuv.pdf
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16136ff7aa1666---numawo.pdf
    • http://85560891.com/upfolder/e/files/20210905202257.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161412100132ee---7980587632.pdf
    • https://xn----7sbbg1ddpkdc.xn--j1amh/uploads/files/84564948316.pdf
    • https://iva-vietnam.com/userfiles/file/3160736974.pdf
    • http://maymaygiaydachidang.com/upload/files/6564282321.pdf
    • https://suadienlanhhanoi.net/upload/files/34130553883.pdf
    • https://livre-d-art.com/ckfinder/userfiles/files/67556901149.pdf
    • http://korvet-sp.ru/userfiles/file/56310802105.pdf
    • https://bevillelecomte.ovh/ckfinder/userfiles/files/74068088729.pdf
    • 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_off0000e220.bin
8d686af878ca91f111a06e4d117d1a85ba545b6285622b586637df044d1db4b3
pdf-font-stream PDF embedded font (sfnt) at offset 0xE220 17372 bytes
font_01_sfnt_off00010f58.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F58 16792 bytes
font_02_sfnt_off0001276f.bin
755897a5a4b92c2eeb373c54f227b0a2d090b4b7e9f1c9655269c9766e8749d0
pdf-font-stream PDF embedded font (sfnt) at offset 0x1276F 10292 bytes