Malicious PDF — malware analysis report

Static analysis result for SHA-256 8138371f7e100369…

MALICIOUS

PDF

86.8 KB Created: 2021-07-05 15:48:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d579e1dad22681c5a44f04d9fc10759b SHA-1: 93fd5a293b838eb4ab2f2ba6cbeaedbc218bec68 SHA-256: 8138371f7e1003699cf4a0f8582c292a30548055e73123b095af4b9ec5870826
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the embedded URLs and the heuristic firings point towards a phishing or credential harvesting attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://philabc.ru/uplcv?utm_term=dungeons+and+dragons+character+sheet+fillable
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/ee407s4ofh35677ercq0mjnla2/bejefuruvaseb.pdf
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16083988bcb33f---81505509392.pdf
    • http://alimentosldm.com/userfiles/file/tijoragefijiwape.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bfaf1eb8eb---53964271195.pdf
    • http://china-hold.com/UploadFile/file/20210516204441584.pdf
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16083868994740---wokaripipisuzuguxavej.pdf
    • https://primer-spb.ru/files/files/veduxojozusaveguvemafe.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/1fec8c5fa784370597ceb6d21b396d3b/sonotofuvakilufuxuxa.pdf
    • http://spl-designs.com/ckfinder/userfiles/files/latojonumikewegifupigeju.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/2bf5e47f0924c4359b706c63879e9a63/10062511017.pdf
    • https://aprilboya.com/userfiles/file/sonegisijiben.pdf
    • http://auto-spec.ca/fck/file/162836575.pdf
    • http://anvlaw.com/userfiles/file/82133208336.pdf
    • http://ruilong-ironwork.com/CKEdit/upload/files/leromenusixijewumukubega.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/24fdc881c1844e2c542999d742ea7def/66927746613.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/sok5ntjijsr18dcdf9pobaehh4/mofebenibufurizuro.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160924430cdd56---2199031717.pdf
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/629ba3d86ac911063d8d99c964c50196/mofejerotubew.pdf
    • http://provia-events.de/pics/fotos/1/file/xuzijojejukubegoxugal.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1606df9c2918f7---fokegupopuda.pdf
    • https://pypconsultores.mx/userfiles/file/6379111153.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/20755b541936a417416ad2578a0c237e/71107116225.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_off0000edf7.bin
1cc6818084191ef55ef00de91b007e9373c54b37f49a45f0d916729e0dcba1a3
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF7 10996 bytes
font_01_sfnt_off0001073f.bin
29e116aae3301043475ac3dc2ff4444308fa329c36a0a1d70b18bf4f26305fd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1073F 17048 bytes
font_02_sfnt_off000133d8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x133D8 16792 bytes