Malicious PDF — malware analysis report

Static analysis result for SHA-256 7e5f1e0c352d50fe…

MALICIOUS

PDF

84.6 KB Created: 2021-09-07 14:13:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 39a7939ec9530452cf4486d9fd7afb42 SHA-1: e73adf6acd8a02336f718d5740aa0cb3eb084d5e SHA-256: 7e5f1e0c352d50fe96c85c8c69c6fc1dd60ddebf82b57e09ba2efa447d97f119
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised or disposable infrastructure, suggesting a link farm designed to obscure the ultimate malicious destination. The presence of a URL with 'pay stub pdf free download' in the UTM term indicates a phishing lure. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nomylo.ru/uplcv?utm_term=pay+stub+pdf+free+download PDF link annotation
    • http://gidromall.ru/img/uploads/file/39865904093.pdfIn PDF document text
    • https://upbilbao.com/ckfinder/userfiles/files/28828255419.pdfIn PDF document text
    • http://midlandhigh65.com/clients/6/68/682e31fde28f8c6bff7ebba57332ef5f/File/xuvotifolomigagisojaku.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/gaporuwezutopidaga.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/62085153161.pdfIn PDF document text
    • http://funperm.ru/content/file/xibuzulodilesuduzilesanun.pdfIn PDF document text
    • https://congchunghadong.com/uploads/files/josejupuvunimeka.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b912a06dd25---kunan.pdfIn PDF document text
    • https://poldercuptrofee.nl/site/admin/ckfinder/userfilesfiles/90443327694.pdfIn PDF document text
    • https://fallahi-sch.com/userfiles/file/danumumejuvad.pdfIn PDF document text
    • https://netkat.in/ckfinder/userfiles/files/79364092322.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077f469e4a92---kesojurixanesipiwona.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-5-5/20210505153126148197.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/15170c56a2da895f25db72fd1a8853cc/vivuso.pdfIn PDF document text
    • https://aquafilling.com/userfiles/file/13230318736.pdfIn PDF document text
    • https://serka.com/serka/upload/files/3989685245.pdfIn PDF document text
    • https://cosmeticdermatologymiamibeach.com/uploads/data/files/74280298825.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160945f3b5c4a8---78025813456.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/ridutiladizukuw.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612c3c7133d46---zitowijizepidugonuloroka.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/5929de1078aab46642e9a97d1f1f3229/64710063065.pdfIn PDF document text
    • https://accounting789.com/ThImg/file/665982064.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080a5cc71c81---9871572530.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/vidugakolevowijujusixara.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f03f6da33cd---3949187032.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_off0000e735.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE735 10840 bytes
SHA-256: b048431ef909812d7ac561db7857e34b40b1a1c0a5690e6b51628c72d43f4701
font_01_sfnt_off0001003f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1003F 17248 bytes
SHA-256: bdbf17858cc3b6cccf4457c9035c293fbe0786723373f41083ab830fd82b99b5
font_02_sfnt_off00012c81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C81 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1