Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cb82cf7eac4590a…

MALICIOUS

PDF

78.5 KB Created: 2021-09-10 08:04:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 502c2ff6210798a2b894b0edf8409df3 SHA-1: 538a38e1973915c58046b6805d584c800365c4fe SHA-256: 8cb82cf7eac4590a610f5c13dc08c2bda53865744352da34622cbb6b73a3c0b4
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to potentially compromised websites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the overall structure and URL analysis point to a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://kawanmto.net/contents/files/41640702717.pdf
    • https://doosradashak.in/ci/userfiles/files/37773023718.pdf
    • http://akekaluck.com/ckfinder/userfiles/files/21325058930.pdf
    • https://www.karelo.com/uploads/File/18099571790.pdf
    • https://pmapmc.com/userfiles/image/files/13286261735.pdf
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f44dd1fd6e---dimuvujodofiwikamitep.pdf
    • http://tele-klass.ru/i/upload/files/nawurokamulazulodamixipe.pdf
    • http://giga.sk/storage/file/sofijagoritoxidufajefan.pdf
    • http://thingsantiquesla.com/userfiles/files/pefukixexofu.pdf
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/riwofigidikibidija.pdf
    • http://riversedgefm.com/files/file/82230403189.pdf
    • http://fotografiafrancescosomma.com/userfiles/files/xeribe.pdf
    • http://speckrepeg.by/UserFiles/files/31156346246.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f79ebef29---jumosapidutamasozubamared.pdf
    • http://brixtontaxi.com/survey/userfiles/files/revofasisapama.pdf
    • https://festivaldelmaridaje.com/sgi_userfiles/userfiles/files/14031841957.pdf
    • http://bajajsports.com/userfiles/file/14455013884.pdf
    • http://secondhandgraphics.com/usrfiles/file/67474107285.pdf
    • https://yp05.com/_UploadFile/Images/file/2241420072.pdf
    • http://shangrilayunnan.com/ckfinder/userfiles/files/96311701228.pdf
    • http://homeopathyhongkong.org/files/26554419360.pdf
    • http://www.gyndoktors.de/ckfinder/userfiles/files/fivexogigefoxawamo.pdf
    • http://konditsionery-odincovo.ru/upload_picture/file/45995597287.pdf
    • http://chpcentre.com/files/file/femusogujalig.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16130ee4360da3---nuzenazopizajizawid.pdf
    • https://easternresources.net/ckfinder/userfiles/files/58041823967.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=friends+season+1+episode+1+free+online+watch
    • 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_off0000cb92.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB92 16792 bytes
font_01_sfnt_off0000e3a4.bin
7330336f749f6bf088ce55e443439f4df7ae20573d4aad27bd7d10891ed41884
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A4 18124 bytes
font_02_sfnt_off000112e5.bin
9af6de9112c8156a85f4c8a5ab231ec4badeff785d0a6d79e01ee08b891c858f
pdf-font-stream PDF embedded font (sfnt) at offset 0x112E5 10832 bytes