Malicious PDF — malware analysis report

Static analysis result for SHA-256 91463db43764ced1…

MALICIOUS

PDF

84.4 KB Created: 2021-06-26 14:15:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7013bc785d974a4262ec8a91de9ee1a4 SHA-1: 24bd0b67350d3531f74d1abde198685f53996a64 SHA-256: 91463db43764ced1216fdad0e1c592daf91bc78b2b14093f10819baf17790cfc
156 Risk Score

Malware Insights

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

The sample was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The embedded URLs, while some are benign, are part of a larger pattern of redirection to potentially harmful 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://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/bd372d57109274276a621629ac3893dd/xomupedijixunigi.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8a52d560d---15820264540.pdf
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe37ad106b---90306337197.pdf
    • http://sahrugs.com/userfiles/file/48028718661.pdf
    • http://tecsun-moscow.ru/docs/file/pezuzeferamuwozavajibe.pdf
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/1a916a756910cc35e16e41b7555dcdb5/88872775707.pdf
    • http://valeneighbors.com/userimages/memepadu.pdf
    • http://asokmontridental.com/userfiles/file/povilolepowopogigeri.pdf
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160ade85fcfea3---jopaj.pdf
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16089cb8b3e5c9---99309617554.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160737196e1c73---38544353227.pdf
    • http://teamwork-poetschke.com/ckfinder/userfiles/files/tonulibamutabi.pdf
    • http://slsnn.ru/content/file/99257692908.pdf
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/99438856107.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/onuod7ng56mj8i8mor3g0tg7ne/vepowawuwagi.pdf
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/fh470krhjqrfu0th17miibhbac/95597053573.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16086a075c467d---44681507766.pdf
    • http://inlygiaylynhua.com/upload/files/5444853067.pdf
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160870f1d0d7b2---fivasil.pdf
    • http://unsersohn.ch/images/file/59673201507.pdf
    • http://2478.ru/admin/ckfinder/userfiles/files/69564497704.pdf
    • http://vankouwenenmastop.nl/UserFiles/file/30205732889.pdf
    • http://www.yoko-ono.be/images/userfiles/file/wobodewe.pdf
    • http://allmedicus.com/userfiles/file/32020225506.pdf
    • http://huile-de-nigelle.info/userfiles/file/kumurejabumujimof.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=child+started+stuttering
    • 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_off0000eae1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE1 16792 bytes
font_01_sfnt_off000102f8.bin
eef9dd136db6f93667210535d0fa6e1ee0ddb4a6047341d83fa10a489b84dcfb
pdf-font-stream PDF embedded font (sfnt) at offset 0x102F8 10536 bytes
font_02_sfnt_off00011aae.bin
122b34038b412813b83e759b2b5a800314fb57959c35ca223cab84580db7c9e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AAE 16152 bytes