Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5e31a370924111a…

MALICIOUS

PDF

77.5 KB Created: 2021-09-19 15:15:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 95064691a88f76b0927537dbc01bfe4a SHA-1: 03744699741497fbccd4c0248d6387051ec53af6 SHA-256: e5e31a370924111af0a48bab8b298bd5393ebcee17bb22411fe039db36636a04
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the primary attack vector is the embedded link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 http://studiosantese.eu/userfiles/files/novumagumupumujesikudu.pdf
    • https://jss-moms.si/upload/File/zulodetegoxumorigesal.pdf
    • http://dreesmann-foto.de/userfiles/file/nalepifer.pdf
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144955171408---zugomoj.pdf
    • http://kovovyroba-nosniky.cz/UserFiles/File/refodesekevi.pdf
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/1478540624.pdf
    • https://www.almuhja.com/ckfinder/userfiles/files/vatuwizumovaditedej.pdf
    • https://tatsolarlight.com/uploads/files/vabebivokelewakajafati.pdf
    • http://yidaig.com/uploadfile/file/20210918075017.pdf
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16134cd777ec0e---botovokibubamizuni.pdf
    • http://kirakuramen.com/uploads/files/74685647244.pdf
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/34184540191.pdf
    • http://medob.org/SITE/files/editor/file/lazurefiz.pdf
    • http://cuacuontoanthang.com/media/file/61460394131.pdf
    • http://tradotel-riviera.com/file/80429986330.pdf
    • https://roofmed.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613f654227da4---46725683367.pdf
    • http://sakra.sk/storage/file/87087733912.pdf
    • http://csc021.com/userfiles/file/20210911154450_m6tbab.pdf
    • http://divyabodhanam.org/userfiles/file/dinovupufeso.pdf
    • http://www.oe.com.tw/ezadmin/ckfinder/userfiles/files/kokipetifo.pdf
    • http://knuhpharm.kr/userfiles/file/20210917053004.pdf
    • https://pastelbuilders.com/userfiles/file/73702401971.pdf
    • http://easyhypermarket.com/userfiles/file/64303006825.pdf
    • http://lltsg.com/uploadfile/file///2021091619085497.pdf
    • https://thokhoavietnam.com/upload/files/ladoturupopiseles.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=pubg+lite+1st+update
    • 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_off0000c4c6.bin
3acd2135a64b2395970c6b7461940a2e3ff04909caa2682118ad08270b7efe7a
pdf-font-stream PDF embedded font (sfnt) at offset 0xC4C6 19700 bytes
font_01_sfnt_off0000f888.bin
ee1270f731dbc7a2b8a9dcd5f79fb9a55ef904ede6337fd24c739405586a52a9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF888 10536 bytes
font_02_sfnt_off00011046.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11046 16792 bytes