Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d66d387c0796b37…

MALICIOUS

PDF

91.8 KB Created: 2021-06-26 06:11:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4b2165ef66b97d83e91f294c3c744c66 SHA-1: 7a539daea3f83a5322d71a74a9e756dbeb387a0b SHA-256: 3d66d387c0796b372a6c2cc9b61bff99fd5123f2b9905b4833274c788dda08d4
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function appears to be redirecting users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://micsys.in/userfiles/file/9993439317.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/mpffil4g9qse7620hupulftco3/41518303517.pdf
    • http://mdsalon.ru/img/lib/file/37051352206.pdf
    • https://tramtron.vn/uploads/files/files/gotirolowoxebu.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1b2584ab1---7115631915.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e72a308edd---78043529880.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a420149810---8546306813.pdf
    • https://tlpnw.com/wp-content/plugins/super-forms/uploads/php/files/9cc8b6c1ec0a53c23ba27ff73899f360/91590281912.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a8106707e39---57159583550.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083df14d1ab3---3136206138.pdf
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b015fcbd966---55917602210.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ac696eeb545---sodowerol.pdf
    • http://bkbflooringusa.com/userfile/abbey/file/zelajizu.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd7419480d.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071841e0c432---finun.pdf
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/5fc573a0710e9962a330512e1bd5d69c/kopejiziburozarazotapusef.pdf
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/9e84e9fbf62ff480ef8a0d3ee4a42da2/mifofezosovasafogin.pdf
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/53a61e6aed57b9ab5672e908f6350a90/80319077844.pdf
    • http://barudan.hk/UploadFile/file/20210525123538530.pdf
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7fa4521bf---karuzuzodo.pdf
    • http://xaydungphongphu.com/uploads/files/bopawerobonatarusu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=low+pass+sequencing
    • 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_off00010344.bin
23a12d1c7544b72b7d1ce0d74b8f6d048e52a5ccc96fa12b071d2b4b297d3f88
pdf-font-stream PDF embedded font (sfnt) at offset 0x10344 17960 bytes
font_01_sfnt_off00013234.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13234 16792 bytes
font_02_sfnt_off00014a4b.bin
a114649d6745b2427a8e9882f7340f70d394a9ba121c91734510bcd7d660191e
pdf-font-stream PDF embedded font (sfnt) at offset 0x14A4B 10592 bytes