Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4278c100288fdfd…

MALICIOUS

PDF

69.2 KB Created: 2021-07-21 09:53:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fe28373b9ba0a475a8b558c817834d1d SHA-1: 64fb41ea3d62fc622769d04cd877a44116f7c813 SHA-256: a4278c100288fdfd57e40c5844c8178a11307c9903315f550cadc9570681765b
154 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting it's designed to lead users to malicious content or phishing sites. ClamAV detection as 'Pdf.Phishing.Trojan' and ML classification further support its malicious nature. The file's structure as a link farm indicates a potential initial access vector via spearphishing, aiming to exploit users into clicking through to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6525

Heuristics 5

  • 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
  • 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://www.520amis.com/upload/files/40648916290.pdf
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/dda223543253cd6ef3924854389fdd27/45747688715.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/ev1767moqp0ed57ttk417p55ma/tajutasi.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/pkhbm1c5sj8e3i65pl83k32kjh/sipepozafaw.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606efa8b68d72---zotuxixurokukojesin.pdf
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/9637ccbfd0354549d40f27d70d28e7c1/dogetazi.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608acc23bc70a---4837925631.pdf
    • https://beyondpins.com/calisma2/files/uploads/41186372665.pdf
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607cfcd2109f6---32266324549.pdf
    • https://hizlipin.com/calisma2/files/uploads/3553140157.pdf
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/nk0iahq4afu6ci52akssgrqei3/2029320564.pdf
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/1ba1737cdeee0620bdd1431dd5eb810e/zekek.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/jpu2dj7mqnfkvrruf2shh8lnr3/purerodeboxinegage.pdf
    • http://banhangcongnghe.com/upload/FCK/file/22802800137.pdf
    • http://accronline.com/userfiles/file/juroled.pdf
    • https://people11people.gr/uploads/File/digojegazonulukemimod.pdf
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/mugazatole.pdf
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/d8fe42e2385210b1c253b60a2518ddcc/77317161758.pdf
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f5475527ef8---jadiv.pdf
    • http://xn--49s538bo8ux8c.net/userfiles/file/67231291750.pdf
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/2892d8fd9291f3dd132909a27d5d3e09/25976314727.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160781ea22924b---badijokovudi.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/0e842cb11610630e3a06de2c16550ba0/mamed.pdf
    • http://tsg-edinstvo.ru/userfiles/file/ruvugivanigezode.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160830d9fc6ca9---27309648804.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=input+type+number+min
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c736.bin
3d20cf7356d849e6bb45ce15a073c00ddddea84feb2e17d23ebe083ec90301bf
pdf-font-stream PDF embedded font (sfnt) at offset 0xC736 20704 bytes
font_01_sfnt_off0000fb74.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB74 16792 bytes