Malicious PDF — malware analysis report

Static analysis result for SHA-256 1836d331a63953c9…

MALICIOUS

PDF

84.5 KB Created: 2021-09-04 17:36:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1cb5f6c1113874886d4fbdc1f854eeb6 SHA-1: 64bb59ca1ae711d4e8726562babadb9b6acb1d77 SHA-256: 1836d331a63953c962cb750579bdddfdd758107c149ba17ba5382f9daf11ad6c
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution lure. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or delivering a secondary payload. No scripts were extracted, but the link farm structure is a common tactic for initial compromise.

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://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/453fedcf9ae0a6c41e6c7dfceeb437ba/13665649029.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160700f7585038---32443927247.pdf
    • https://tdfstore.it/file/wilok.pdf
    • http://lagrupacio.cat/file/gutejodimaxipode.pdf
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160764380366b9---pelokabawexeveputip.pdf
    • http://christopherdallo.com/file/kalor.pdf
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2bcfd837b---42066978479.pdf
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/4pajj8admrrs5o86p7mvru0d25/bovatekeruj.pdf
    • https://108pizza.pl/uploads/userfiles/files/rewutu.pdf
    • http://lammensfilip.be/uploads/files/58398541504.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb950f3c0e---semejitu.pdf
    • https://penzion-pod-rozhlednou.cz/img/file/9197010603.pdf
    • http://kronikarp.pl/ckfinder/userfiles/files/65692157729.pdf
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/gijuzigozo.pdf
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/9d3a370aeff8f5dc39886f704cddbafc/fonexadu.pdf
    • http://adabaskimerkezi.com/upload/file/31964056259.pdf
    • http://tovicetour.com/FileData/ckfinder/files/20210730_F26367443A5829D2.pdf
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/16114fc59612ab---72442221266.pdf
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093ad5401a72---56345084766.pdf
    • http://bobiniauto.com/userfiles/file/xemavedepanaboxer.pdf
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/c15b2bffb7c0c9534307d8c4ce4b0b0e/sajejefovez.pdf
    • https://xehowo24h.com/images/ckeditor/files/xipogivofefola.pdf
    • http://iglozawiercie.pl/zdjecia/file/94067512170.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160a0a3fe05ab0---36740671121.pdf
    • http://bestbelly.org/content/files/files/38571833953.pdf
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab3859e908---maleve.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=exercices+sur+les+valeurs+du+pr%C3%A9sent+de+l%27indicatif+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_off0000dc64.bin
b935146786fe25bdbecec10aab1e9129e6c4d38194c9c518fda1aa5a6d4774b5
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC64 20840 bytes
font_01_sfnt_off00010ff0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF0 16792 bytes
font_02_sfnt_off00012807.bin
edf38b1c2bdd57da19f6e9ea56abfe486e690037a1fae56db4fdcfbbfbe7a5a1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12807 10932 bytes