Malicious PDF — malware analysis report

Static analysis result for SHA-256 8809bb115161712a…

MALICIOUS

PDF

101.1 KB Created: 2021-09-17 13:42:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aaf7291d0f121aa1c82064855377eef1 SHA-1: 847f07e8bb09395d6c20ffcf4a01597af6b49223 SHA-256: 8809bb115161712a5a967b95226d1a17fea2379368af82ee6ad8101ec1bbfc65
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. Several heuristics indicate the PDF is part of a link farm pointing to potentially compromised websites, suggesting a phishing or malware distribution scheme. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=android+os+service
    • http://homestayhoian.vn/uploads/image/files/fudolisemonej.pdf
    • https://duvanco.be/docs/files/dukagokejeput.pdf
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/75658032365.pdf
    • https://mitrasuksesku.com/userfiles/file/xurodaxajesigodokavikus.pdf
    • http://sun-marche.com/app/webroot/js/ckfinder/userfiles/files/wefigigudurikajeju.pdf
    • http://zvaracskaskola.eu/editor_uploads/system/files/tosuwerivofumumosokez.pdf
    • https://yuktogel.com/contents/files/81407931571.pdf
    • https://pasifikendustriyel.com/userfiles/file/mibibak.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614456f4db645---13837267586.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161367577a7199---9116532725.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/ackte64h37pd70pfqd7dl6dj9u/tuduximekinofen.pdf
    • https://fsreloading.com/userfiles/files/66834191939.pdf
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/1597ae56a432e87a6b0e91befa4f9a38/lipinabum.pdf
    • http://doktor-okonski.pl/uploadimg/file/revoxekaw.pdf
    • https://2winit.com/Files/files/54957151405.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/161310dceb4b2b---54355032271.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614144c4ea99f---80406445871.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132af256ad26---31900009328.pdf
    • https://dallaslandscapedesign.com/media/files/10612035759.pdf
    • http://china-miyaco.com/img/file/20219685743.pdf
    • http://chiaranannini.com/userfiles/files/ravufunexumonimedewoxurep.pdf
    • https://loyd.rs/images/file/84746708791.pdf
    • https://www.iieng.org/editor/ckfinder/userfiles/files/rumizifugujavexobarelazi.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_off000126c3.bin
0f15c345d626b3a4cbd9f5eb2ea1da70b95abeeba2bfe3d61e0cdf8df54a6496
pdf-font-stream PDF embedded font (sfnt) at offset 0x126C3 10104 bytes
font_01_sfnt_off00013d71.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D71 16792 bytes
font_02_sfnt_off00015583.bin
77c6e9658840ffd99d62765ba520c0720b79cce95de6ddf53f312288773ae750
pdf-font-stream PDF embedded font (sfnt) at offset 0x15583 18700 bytes