Malicious PDF — malware analysis report

Static analysis result for SHA-256 85c7d28a91f7e45b…

MALICIOUS

PDF

85.8 KB Created: 2021-09-18 07:58:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: c8336cd6e8302c6a8a6c095123bfde4a SHA-1: 26eb480d0be463c3ebadcbc65b234b8bae47cc44 SHA-256: 85c7d28a91f7e45b825c59ecb434acd83d52b47cf04020da9fbac1627eebc601
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links to external websites, many hosted on compromised or disposable domains, suggesting a phishing or malware distribution campaign. Although no scripts were explicitly extracted, the PDF structure and link farm nature indicate an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://garglob.ru/uplcv?utm_term=english+exam+for+beginners+pdf PDF link annotation
    • http://aescantabria.es/upload/fckeditor/file///7239008073.pdfIn PDF document text
    • https://anitacalderon.com/ckfinder/userfiles/files/vumepinofodobobakaxumij.pdfIn PDF document text
    • http://skolky.info/foto/images/file/21553409936.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-9-15/20210915221627944286.pdfIn PDF document text
    • http://globalroomplus.com/bot/ckfinder/uf/files/punamofujovirevotukuxig.pdfIn PDF document text
    • http://captaincook.hu/userfiles/file/wejozopubojoponazakom.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/fidibovix.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141c0f337729---86997828697.pdfIn PDF document text
    • https://alident.centralcms.cloud/galeria/files/rovidonibetivux.pdfIn PDF document text
    • http://arsvet.ru/img/upload/pularonugetenep.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133648dd8b3c---57023287624.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/jb700i0etnjjotdjc1mpfsdrm1/fasolitukasir.pdfIn PDF document text
    • http://radtel-sport.pl/userfiles/file/jujetawesitixumolono.pdfIn PDF document text
    • http://mariautonoleggiomarsala.it/userfiles/files/jenelunojasakasukoxis.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/wegutatokujotuke.pdfIn PDF document text
    • http://parzenica-bialka.pl/userfiles/files/fuwijekobe.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/12928802262.pdfIn PDF document text
    • http://petukmahaaaraj.com/userfiles/file/84272753873.pdfIn PDF document text
    • http://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/rojenurevimedegovivuso.pdfIn PDF document text
    • https://chetanaus.org/bheru/uploadfiles/file/89221274729.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_off0000ec2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2D 17232 bytes
SHA-256: 4edb1bc3c77641dbce777367a305e507ccd136cc98a6a0795a59bb2f2fab88e2
font_01_sfnt_off0001189a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1189A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000130b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130B1 11072 bytes
SHA-256: 002da57ac98bd98b2ae2049dce5072c3cb88bc4a87d39a666df8a4f797bf2a70