Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8151b74fbdefb1a…

MALICIOUS

PDF

74.2 KB Created: 2021-07-06 18:55:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 855aa825bdb7665c30b874ee871fc34e SHA-1: 8fba51ac0b9c3264924f182b49d3320062a8435b SHA-256: a8151b74fbdefb1a73767b1c22177b7e7ef765c84efffb4be62a9f468b1ef9c7
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting it functions as a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The presence of multiple external URIs and link farm heuristics supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://smidgel.ru/uplcv?utm_term=clayton+county+ga+jail+inmate+search
    • http://clarasonic.com/upload/file/laronilelufojalizerakuju.pdf
    • https://sokolzgierz.pl/web/uploads/files/34735910549.pdf
    • http://shethof.ch/cgi-bin/dynamisch/file/86240840157.pdf
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/fed002c5fd267028fe6962c21bd17f43/36393274527.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4aac64e0a---vipod.pdf
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8f32eb2ca0---tisafavijowod.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/7800375ea133b4596d8e58f79eee9e19/10967277819.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1607d74487ace5---54238621063.pdf
    • https://tenshinorchids.com/FCKeditor_upload/file/4300759052.pdf
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/160e33f8328b49---88467169841.pdf
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/1608dbecfcddf4---napunimopogobanisodibu.pdf
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a00e6448720---tezebonuju.pdf
    • https://t2sc.me/userfiles/10036941004.pdf
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5743170a96---57200665222.pdf
    • https://cytairtool.com/test/userfiles/file/20210703_a1f6a.pdf
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/hpcnf5sj8cbq9o1dv14ga32esv/vogopumoregobuja.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a53b4018520---savaxigurevobarife.pdf
    • http://turatabor.hu/media/sexatixuvuwurukumaxafer.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fd0859d3e0---dusinazijanunon.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/ifi8pplt1tfcs1c86jr7hhi85g/dijidujuno.pdf
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/jasof.pdf
    • http://codemessaging.net/ckfinder/userfiles/files/demun.pdf
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/d81f23c47588f603522307324369103e/sifaf.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_off0000bee5.bin
1831abacc9ada521d083d9e84b8e5cd52c07e5eb5e821ca0d2912c722ca06542
pdf-font-stream PDF embedded font (sfnt) at offset 0xBEE5 16288 bytes
font_01_sfnt_off0000e9ae.bin
d1836e32b0f948048be0f2374cfd2893b46ebe2d58d5b07d9201f54bb987afc4
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AE 11052 bytes
font_02_sfnt_off00010347.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10347 16792 bytes