Malicious PDF — malware analysis report

Static analysis result for SHA-256 f793b53ee739e9cd…

MALICIOUS

PDF

78.2 KB Created: 2021-09-21 00:05:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 406a85d6fbe8a79583a1be38cf57f0c6 SHA-1: 21dee5199bc0c44c9709baca2c0fc2752d0cc6c0 SHA-256: f793b53ee739e9cd6e387fac1de5632fb927027dadee24500bb1011e33e1b5fc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised websites 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 malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://philabc.ru/uplcv?utm_term=mortal+kombat+shaolin+monks+iso+ppsspp PDF link annotation
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1614301b3c6110---73627274993.pdfIn PDF document text
    • http://monteconsultants.com/image/upload/File/tukulexawos.pdfIn PDF document text
    • https://aspirecambodia-edu.org/userfiles/file/fivolakas.pdfIn PDF document text
    • http://autostyle-japan.com/js/upload/files/90960509955.pdfIn PDF document text
    • https://nls.vn/upload/files/13572603862.pdfIn PDF document text
    • https://izometal.net/mm/file/lesojibodesuvujijuzogiso.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/72390246096.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/p4o8eb9fq1dehekslams60kopm/10576531588.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f6e4080211---keripasoluko.pdfIn PDF document text
    • http://gesundezellen.com/neu/userfiles/file/gurud.pdfIn PDF document text
    • http://geose.ru/userfiles/file/15956177141.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/vuvuniwotifiruxazifudun.pdfIn PDF document text
    • https://adikketiga.com/contents/files/sorereligonakudobeb.pdfIn PDF document text
    • http://chothuexeninhbinh.net/data/dulieu/files/xekefatarogefisurilij.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/2bsoa75jpb71qsfev17ia7lda5/mopakufusisiroxugiku.pdfIn PDF document text
    • http://dakmoto.cz/obrazky/file/fenota.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16148f65fd5843---50955724036.pdfIn PDF document text
    • http://3dsami.org/uploadfilefiles/gapemoj.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/967e402d1afe80c2b4276ecda47df95c/3846356039.pdfIn PDF document text
    • http://vucert.vn/uploads/files/mobiz.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/53769456163.pdfIn PDF document text
    • 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_off0000cd42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD42 10612 bytes
SHA-256: fc624a1be1757f2feb2278edaecb7f02b3c4f6de0fcb75098b2e88353e597f4a
font_01_sfnt_off0000e512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE512 17660 bytes
SHA-256: 1a737605c2140aaaac0f9952383012d8cd08a4d5132806fb5acd298b7302eb52
font_02_sfnt_off00011333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11333 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1