Malicious PDF — malware analysis report

Static analysis result for SHA-256 442ce8fb5901674f…

MALICIOUS

PDF

80.5 KB Created: 2021-09-12 00:00:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b91cc9bdfe21bf5c1c4769f660c0f884 SHA-1: 7941c153efaec93138c62098c44603ab7d890055 SHA-256: 442ce8fb5901674fe45bcc7fd29be9bbdabd1dc22f552c4143a9fd99f5028935
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://tubesealer.com/uploaded/file/343002624613a612e8bc31.pdf In PDF document text
    • http://altronic.pl/!mag2011/userfiles/file/gaxamalixakov.pdfIn PDF document text
    • https://ciar.vn/uploads/image/files/14325441290.pdfIn PDF document text
    • http://pvvc.cz/files/felof.pdfIn PDF document text
    • https://arrad.ch/modules/ck/ckfinder/userfiles/files/sudigivimukada.pdfIn PDF document text
    • http://maginsaatmetal.com/resimlerfiles/90466477505.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137d23b6d998---samusiwuxokibonixidiw.pdfIn PDF document text
    • http://greenearthgardens.org/userfiles/gikaxigobeze.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.org/upload/files/3388144300.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/3cmgrtuf1ac4mj97e1mpok61uk/gamejalili.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/82181892065.pdfIn PDF document text
    • http://luxlustry.ru/img/upload/42991438104.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ace75d1baf---68029126854.pdfIn PDF document text
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/84535993749.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/c3d49493aba8bd8773a14a12d99e7bea/13934844956.pdfIn PDF document text
    • https://gesema.com/UserFiles/file/15196915451.pdfIn PDF document text
    • http://riviera.az/userfiles/file/bumal.pdfIn PDF document text
    • https://12shio2.com/contents/files/99767743354.pdfIn PDF document text
    • http://uktohabbarijamalta.com/files/file/52622757148.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354d61da391---lizarogekamotisil.pdfIn PDF document text
    • https://mlbcsimleague.com/ckfinder/userfiles/files/99551002239.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=minecraft+minecraft+free+for+androidPDF 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_off0000d458.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD458 18596 bytes
SHA-256: e0a54a947ef41dc4f15eabd19f10f6726116302456426c76696f71af2028f248
font_01_sfnt_off000104d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ce7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE7 10416 bytes
SHA-256: 21db6f8de8ddf75767ecc3336cb155a2f48647b18b5054b5281800e009350dd5