Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d5839e56370c8bd…

MALICIOUS

PDF

77.9 KB Created: 2021-07-21 09:53:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3511505c41c87d711498e241529d5390 SHA-1: 41eed402ea1153f4e97b1ad19242a7c8d04a3a59 SHA-256: 9d5839e56370c8bdf42df1b2a7577e345dee1b58ad73592eec3e8a47f529b41c
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites hosted on compromised WordPress installations and disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable binary data.

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://www.520amis.com/upload/files/40648916290.pdf In PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/dda223543253cd6ef3924854389fdd27/45747688715.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/ev1767moqp0ed57ttk417p55ma/tajutasi.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/pkhbm1c5sj8e3i65pl83k32kjh/sipepozafaw.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606efa8b68d72---zotuxixurokukojesin.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/9637ccbfd0354549d40f27d70d28e7c1/dogetazi.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608acc23bc70a---4837925631.pdfIn PDF document text
    • https://beyondpins.com/calisma2/files/uploads/41186372665.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607cfcd2109f6---32266324549.pdfIn PDF document text
    • https://hizlipin.com/calisma2/files/uploads/3553140157.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/nk0iahq4afu6ci52akssgrqei3/2029320564.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/1ba1737cdeee0620bdd1431dd5eb810e/zekek.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/jpu2dj7mqnfkvrruf2shh8lnr3/purerodeboxinegage.pdfIn PDF document text
    • http://banhangcongnghe.com/upload/FCK/file/22802800137.pdfIn PDF document text
    • http://accronline.com/userfiles/file/juroled.pdfIn PDF document text
    • https://people11people.gr/uploads/File/digojegazonulukemimod.pdfIn PDF document text
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/mugazatole.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/d8fe42e2385210b1c253b60a2518ddcc/77317161758.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f5475527ef8---jadiv.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/67231291750.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/2892d8fd9291f3dd132909a27d5d3e09/25976314727.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160781ea22924b---badijokovudi.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/0e842cb11610630e3a06de2c16550ba0/mamed.pdfIn PDF document text
    • http://tsg-edinstvo.ru/userfiles/file/ruvugivanigezode.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160830d9fc6ca9---27309648804.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=input+type+number+minPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c736.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC736 20704 bytes
SHA-256: 3d20cf7356d849e6bb45ce15a073c00ddddea84feb2e17d23ebe083ec90301bf
font_01_sfnt_off0000fb74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB74 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001138b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1138B 10220 bytes
SHA-256: a1eac5ab16120f9f8a93ed25ebc64bc3b4d2debbfc8e07369f68c248e7db6a35