Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc22c6db7a70c693…

MALICIOUS

PDF

85.5 KB Created: 2021-07-12 23:38:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9754864c5ed3a6cd6ee2ace166e5b1dc SHA-1: 1735f071d6edac452c2b146b8ac37d6c59ca4fbc SHA-256: dc22c6db7a70c693e8c0ba211fc03f0589298cf1cce58ba49cdef9d029906f16
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS upload storage or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely involving exploitation of PDF vulnerabilities to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://medvor.ru/uplcv?utm_term=fifth+water+hot+springs
    • http://superlitefan.com/uploads/files/23365579259.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c74884b87---timogukifo.pdf
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/344797739c92cf47112ec3dd6eded696/8436725566.pdf
    • http://cybernet.asia/UserFiles/File/33000264631.pdf
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/6afe38d34cccb72152ed093bb0ab9e13/tavujujudizuzerazedumifa.pdf
    • http://surmounttravel.com/userfiles/files/24848092454.pdf
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608a265a8c3ba---jidawatekozer.pdf
    • http://gagutp.com/sa_upload/userfiles/file/20210613040127.pdf
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/16090bd878886c---13523381546.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160837114e08bd---bugosupilela.pdf
    • http://bestapp4u.com/admin/uploadedfiles/file/gekivababivarulorudozuto.pdf
    • http://djarkitek.com/temp/vinney/HTML/userfiles/file/43842509187.pdf
    • https://ooo-kenk.ru/userfiles/file/45845931533.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/jlemnremvctujg7vn4jihoh390/62417767750.pdf
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b75f3ba0808---51660962150.pdf
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/fcda63a9b56eb2d77c2547fbfd06e8f5/4379227044.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160804547992bd---gexomilugizasodelu.pdf
    • http://www.aqsclimited.com/EditorImages/file/taxakuvegukorasuveboruvuk.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9c430d8740---suzomikisemagovasabir.pdf
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/4f427b8dd3b0cc0db39409f1ce731b65/58566297929.pdf
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/36f50d2491a5c60e1f2ed3c46bfd5b74/dabetikixosekufa.pdf
    • http://mudrkanuch.sk/editor_uploads/system/files/46230026412.pdf
    • https://menu2uplus.com/images/file/fuliwonarumiwazakudekalu.pdf
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/a0e37217e7c8e714e49675b13fead276/wuzugoniger.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_off0000e790.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE790 16792 bytes
font_01_sfnt_off0000ffa2.bin
06f2e2d392ea2c1d8eaafa526a25508d73d447acf7f48e7386801a857abe96a5
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFA2 17892 bytes
font_02_sfnt_off00012efa.bin
5f7dc2948583ff72d91d118595b8697066070b1cc26a433ca0421718d1285c8f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EFA 10656 bytes