Malicious PDF — malware analysis report

Static analysis result for SHA-256 985d75f4fcef4052…

MALICIOUS

PDF

90.8 KB Created: 2021-07-03 17:02:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e54f452c15a11fd1cd6cef554687ced9 SHA-1: b0026c95370038ea0549f5a40301bf8d4b4e8af5 SHA-256: 985d75f4fcef405200298263a9c3a4454c64bbaefaa157902c93ee97654036da
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external URLs, several of which are hosted on compromised WordPress sites or disposable domains. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://synerhu.ru/uplcv?utm_term=yellow+tail+cribo+snake+for+sale
    • http://gazosilikatnn.ru/uploads/files/tudiwotu.pdf
    • http://ucity68.com/clients/e/ea/ea220da86df44fb0ae3b7c8e8295ccc1/File/xutajuxezovuno.pdf
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/94368237540.pdf
    • https://smilepaper.tw/archive/upload/files/37913331893.pdf
    • http://niengrangchuyensau.com/upload/contentFile/file/26472654273.pdf
    • http://www.ecostroyservis.ru/File/muvotagowaxiluxerup.pdf
    • http://originalcheck.it/public/img_admin/file///rujarobebalisuromatobexef.pdf
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fb5ec9b8e6---84169036912.pdf
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609420f081c79---vepusipom.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160913068ddcd6---99137534030.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e52c157bc.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160712d241995e---2167202470.pdf
    • http://bmhs1963.com/clients/7/72/7286fd37811b7a5dece6e69924e4d5ab/File/3463094401.pdf
    • http://lab4050.com/upload/editor/file/vuwibot.pdf
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/2633bce7d2ce125cfa20c37e2f70546c/zilomuwidodedelofalepoxit.pdf
    • http://cphs1970.net/clients/877309/File/jogifekuwupab.pdf
    • https://www.basur-tedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c4d1e2739---bonirotujapuvepesi.pdf
    • http://egonseetour.com/FileData/ckfinder/files/20210623_562069E3085D1CCE.pdf
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/5b90c14ae83670ebacb47a6a735ba26a/18195149954.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608af08f9f768---zimiwariv.pdf
    • http://alkanboya.com/files/file///68552372215.pdf
    • https://geneolock.com/locktactyuma/userfiles/file/wikesugud.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_off0000fddd.bin
0e3d678163849b4f28b8d75289c38e8d69fef92fbdb3e9a4bad0bb71da4d3af8
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDD 10628 bytes
font_01_sfnt_off0001165b.bin
21b1d651615a24c67e1c20b2a20c928b493116b0d2acd13f9f9389a3a03df620
pdf-font-stream PDF embedded font (sfnt) at offset 0x1165B 17712 bytes
font_02_sfnt_off00014452.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14452 16792 bytes