Malicious PDF — malware analysis report

Static analysis result for SHA-256 7961f2b758d8a3c0…

MALICIOUS

PDF

93.3 KB Created: 2021-09-18 21:21:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 23052562ee3b372733143c4c63e5a11a SHA-1: 7b2e5c78501b01d3d3cc4db5845ed12d9ef0b248 SHA-256: 7961f2b758d8a3c06326bb5aa1e4a445e18d1f114871d3c567cacbf2e16998c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or are hosted on disposable domains, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier further support its malicious nature. While no scripts were extracted, the structure and URL patterns are consistent with phishing or malware distribution lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9897

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://kermanrooz.com/img/files/debadujebum.pdf
    • http://dichvumucin.com/upload/ckupload/files/36490902540.pdf
    • http://majstrissmt.eu/www-data/file/xedatuporosivexomogoj.pdf
    • http://tsradviseurs.nl/mailing/images/photo/file/kafanuvipujupolezesifed.pdf
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/zuvotirex.pdf
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/kog8snfvn8hgarbbjiblq32bfe/84220736025.pdf
    • http://www.alfapilates.pl/upload/file/rinabuwivodogiw.pdf
    • https://tekdalyapi.com/upload/ckfinder/files/45935464324.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145dd0652a4d---56143958424.pdf
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/3d87e3074a6bcb8633c81c51c6e2eec1/30067462504.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16130229bef6df---25186916812.pdf
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134b18baf410---bulemat.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408ae6306e3---dujozu.pdf
    • https://latework.cz/soubory/28873689251.pdf
    • https://dveropolis.ru/upload_picture/xusudewumakutigaleditowo.pdf
    • http://kamienneogrody.com/userfiles/file/saxatosabejagexuwuzap.pdf
    • http://hophungvietnam.com/app/webroot/uploads/files/xukavapazot.pdf
    • https://woodfur.in/userfiles/file/40228296487.pdf
    • https://iieng.org/editor/ckfinder/userfiles/files/36382064006.pdf
    • http://theexplorerthai.com/userfiles/files/40514406407.pdf
    • http://yishiweb.com/upfiles/files/20210909_032128.pdf
    • http://turnwealthy.com/ckfinder/userfiles/files/masus.pdf
    • https://defi128.com/userfiles/files/jurokifomabebufate.pdf
    • http://yas-center.ru/userfiles/file/rodam.pdf
    • http://dolinakrzeptowa.pl/public/upload/ckfinder/userfiles/files/mujoluxopiwegupugizedetu.pdf
    • http://cuacuonanbinh.com/userfiles/file/miparuko.pdf
    • https://s-serviss.lv/userfiles/file/96337994445.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=screen+unlock+software+for+android
    • 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_off000109f5.bin
41c821392398463b94852c0a97d6a1820bc3209ec7afd450ce24db242ac835c3
pdf-font-stream PDF embedded font (sfnt) at offset 0x109F5 16924 bytes
font_01_sfnt_off000135c0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x135C0 16792 bytes
font_02_sfnt_off00014dd7.bin
294beb11922083da4dfbe62b22053be39c5e601ba03f150c4ee5e9e8b6ca5ac3
pdf-font-stream PDF embedded font (sfnt) at offset 0x14DD7 10824 bytes