Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfbe0eb9500efc03…

MALICIOUS

PDF

76.4 KB Created: 2021-07-01 00:25:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f63d5f6c5408205a8aa90ec5c8bc650d SHA-1: 3cf5986d685ce6c5f6def1badc633afdcf4e7e2d SHA-256: dfbe0eb9500efc03a2ba53417af3849fe109f262f7a4a2a7fd173f2896b5daab
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It contains numerous embedded URLs pointing to compromised websites and disposable hosting, suggesting it functions as a link farm for phishing or malware distribution. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for human readability but rather for programmatic exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=the+rate+of+a+first+order+reaction+is+1.5
    • http://mya1fc.com/files/ckuploads/files/58495647265.pdf
    • http://anhuizpyy.com/upload_fck/file/2021-5-25/20210525044941698653.pdf
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/cb58d4772c23fa2bcd460e736a31e7fb/silafexomorexonodijuwok.pdf
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/bd5474d4d8d6131410ef9098276f305b/noxobiluwebaxipeguf.pdf
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/bf0847a904ad81e4f7a0d889a5f3b2ee/kuxekidafetunulupowilolu.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/fdqj5morvcsssruem461tngrgv/55504557374.pdf
    • http://www.hussco-steel.com/husscofiles/files/gixukewejedo.pdf
    • https://eyetracking.pl/userfiles/file/54018130526.pdf
    • http://nextgenship.net/upload/file/20210613162358198112.pdf
    • http://polymer-optix.de/userfiles/file/56198961964.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160791c1a14733---23941095037.pdf
    • http://carroll1975.com/clients/4/4e/4e2b018d07aaa5a30c3e4fca1c7a8df7/File/87239355006.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16080612fae33d---74755331126.pdf
    • http://nw-line.ru/generic/uploaded/defilexutalere.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/fb938784b95c6c2bca4217c4efde6732/jodaweraniw.pdf
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/82ef1facd4174d68768352d3fa73c6d8/18991332920.pdf
    • http://www.cenlafilm.com/siteuploads/editorimg/file/pokuwedegalumixa.pdf
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/00ba4fd9914f6c00d59dc879d8ce451e/ledanit.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/heofcbhgriosd893lp0tabhenq/41953814821.pdf
    • http://recrute.fr/files/files/mejadakepaxegivagabe.pdf
    • http://puzynowska-kancelaria.com/userfiles/file/kirogupifid.pdf
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/d45a4a6555d325e25eb5371ba5a07daf/2998592492.pdf
    • http://aylincinarli.com/fckfiles/file/zifisigifirivemipip.pdf
    • https://puppometalli.eu/file/26210225118.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160baef34b95a9---ponesavexuxapowomegawubu.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_off0000c5b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC5B0 16792 bytes
font_01_sfnt_off0000ddc7.bin
2abeda9ddb68f9ebfb0d637442af0c70730659f10653309a42ded6596650170c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC7 10744 bytes
font_02_sfnt_off0000f688.bin
5bebdde6b94767e517dbcb4aa02b405e951aabd536c357b159a0e072ed811a3c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF688 17348 bytes