Malicious PDF — malware analysis report

Static analysis result for SHA-256 640b7c9e51d9f0ee…

MALICIOUS

PDF

75.7 KB Created: 2021-09-18 01:02:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 979e66ee13d552fb7d586494683d1f00 SHA-1: 9e5c3f4cec54caf8281d4d06327019b3e2ff5537 SHA-256: 640b7c9e51d9f0ee997a7c141796778a5d7f7ec2582313159b70e5e1834e1f01
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://huntic.ru/uplcv?utm_term=pubg+lite+bp+to+bc+generator PDF link annotation
    • http://olympusflights.com/files/files/japogiv.pdfIn PDF document text
    • http://domki-kopalino.pl/pliki/libade.pdfIn PDF document text
    • http://kprmk.pl/userfiles/file/nirosi.pdfIn PDF document text
    • http://8njl.com/userfiles/files/wogodapasibumidizumixa.pdfIn PDF document text
    • http://burchiellati.com/file_fck/file/jigakagudoruzomaf.pdfIn PDF document text
    • http://mhfmjournal.com/data/22/2/55/64/2544879/user/2788947/htdocs/userfiles/file/30405447441.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/e62f51296bfa3464a0be2a7787d39bc8/19187479767.pdfIn PDF document text
    • https://stancijanegrin.com/UserFiles/files/66446110742.pdfIn PDF document text
    • http://sanyosushiglendora.com/uploads/files/52913934232.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161450cbb1238d---35755973499.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/12809368529.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/sogakopepumovowiboto.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/vg9p766k8gb2vbvlo85dsgblem/fokejul.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/saritamamudevupepavak.pdfIn PDF document text
    • http://ladna.pl/user_images/file/1061621599.pdfIn PDF document text
    • http://sro52.ru/uploads/files/90948877172.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-18/20210918050612536641.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/24698577265.pdfIn PDF document text
    • http://svx.su/ffile/file/wuxugenalusozidumiperer.pdfIn PDF document text
    • https://datenglagi.com/contents/files/23103196828.pdfIn PDF document text
    • http://pokebarslo.com/uploads/files/46704871026.pdfIn PDF document text
    • http://guerrazzi.info/userfiles/files/68689458324.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_off0000c5a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5A1 16972 bytes
SHA-256: 48fbbb9da88d9c97fa3fbf8a51744886bf053f2dc4ab82c74a9cedca47e1786d
font_01_sfnt_off0000f175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF175 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001098c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1098C 10624 bytes
SHA-256: 93e425f6130dec92b7f242a6f4bef223d9f0f0e6824f225ca4fdaec48372f8e6