Malicious PDF — malware analysis report

Static analysis result for SHA-256 99c77b90071cd878…

MALICIOUS

PDF

74.8 KB Created: 2021-09-18 08:11:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f3550e6127bd7093cb8ee61865e76efe SHA-1: 7fdee53c5cbd6948d741beb61387b69df04d46a5 SHA-256: 99c77b90071cd878761b60b3ea078fb7f42fca9d1228104752959509ecc96972
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is unreadable, but the heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://medvor.ru/uplcv?utm_term=cyberpunk+2020+blackhand%27s+street+weapons+pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141082d81913---52986133778.pdf
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/16140d58fc80a4---23123317811.pdf
    • http://humanitool.ru/userfiles/file/wagon.pdf
    • https://cincia.ro/ckfinder/userfiles/files/82444737203.pdf
    • https://medicabg.com/uploads/wysiwyg/files/66234868604.pdf
    • http://tfh-filter.hu/_user/file/bobudakanino.pdf
    • https://branpc.in/ckfinder/userfiles/files/kulufoxibobofabopovipuvof.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137abbbc351e---92671316742.pdf
    • http://hamlineparkplaza.com/assets/amund/ckfinder/userfiles/files/41822046748.pdf
    • http://medianet2000.net/amm_prod/image_news_popup/file/mopuzizefifapirona.pdf
    • https://zebcom.in/userfiles/file/26714382546.pdf
    • https://fuze-pay.com/ckfinder/userfiles/files/75091574835.pdf
    • http://artattack-concerts.de/files/file/46297308381.pdf
    • http://herium.net/FileData/ckfinder/files/20210916_7FD343134369F37F.pdf
    • https://monographie.com/ckfinder/userfiles/files/rifanexexamumeku.pdf
    • http://studiolaviano.it/userfiles/files/pefima.pdf
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd8a603a65---zenarerobareromamap.pdf
    • http://www.letnifestiwal.pl/ckfinder/userfiles/files/vasowu.pdf
    • http://laboratoriodiprogettazione-ve.it/userfiles/files/35830297078.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131c46470a67---pakatukabagelogeme.pdf
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/90073453703.pdf
    • http://presssimayeshahr.ir/pic/file/xidonetapa.pdf
    • http://wienbildarchiv.com/upload_files/files/nopedasezowiwaxo.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_off0000bd2a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBD2A 16792 bytes
font_01_sfnt_off0000d53c.bin
439cb872c8f0af3482b3aa3408fe5b57bc25c05f850064954326d96830ba9a0a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD53C 17516 bytes
font_02_sfnt_off0001025a.bin
94ce42baa1202444213d91d242d24e78c056aad72a4f251e4038f5f2f217660b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1025A 11464 bytes