Malicious PDF — malware analysis report

Static analysis result for SHA-256 5e5ae85cf4a233a1…

MALICIOUS

PDF

74.9 KB Created: 2021-09-24 09:42:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6024744a423ef84351b4a7b6362f660b SHA-1: 826911b33a331036895642b60b6e1bd14210432a SHA-256: 5e5ae85cf4a233a1920d6f8c2e9835d04e3408ae4b59eb45ad36f725cb520d4f
196 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'SE_BROWSER_INSTALL_LURE' strongly suggests the document is designed to trick the user into installing unwanted software, such as browser extensions or updates. While no scripts were directly extracted, the presence of numerous embedded URLs, many hosted on compromised or disposable domains, points towards a phishing or malware distribution scheme. The document body is heavily obfuscated, preventing a clear understanding of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://sieuthimaytinhcu.vn/upload/files/sigakezowo.pdf
    • https://licorne-hotel-restaurant.com/userfiles/file/xixobubetusabenulalubam.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/161334420d2f66---gerofapopuputaxelagekum.pdf
    • https://www.tamilsaga.com/ckfinder/userfiles/files/68130295999.pdf
    • http://bsp-plovdiv.org/ckfinder/userfiles/files/gevirodewawakawodirepo.pdf
    • https://movingalpsfoundation.ch/userfiles/file/37277921280.pdf
    • https://silky.ae/images/bulk_images/files/vewobo.pdf
    • https://minlinart.com/archive/upload/files/9512377840.pdf
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/10513554010.pdf
    • https://foodphotoshop.com/userfiles/files/wotirivopiv.pdf
    • https://cleartunemonitors.com/ckfinder/userfiles/files/64214636775.pdf
    • http://work4shop.cz/userfiles/file/73719015560.pdf
    • http://wakabaeducation.com/userfiles/file/zuxililonobof.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161365c09be143---1907779547.pdf
    • https://buyafranchise.org/files/files/77833558168.pdf
    • http://coomargroup.com/ckfinder/userfiles/files/43419596788.pdf
    • https://rzfmuhasebe.com/userfiles/file/nusag.pdf
    • http://askaudit.ru/price/gisalojiwomibavagoru.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133dcd3b5ab8---85712258136.pdf
    • http://bimbrlata.cz/UserFiles/File/vuwuxupo.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ede6e20ef7---wilaxawoza.pdf
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613c1c7189995---55951706841.pdf
    • https://seerupit.dk/assens/file/kaniloluvunodowusamur.pdf
    • http://karmakonnect.org/DrumiBhatt/karmakonnect.org/Final/ckeditorimage/files/pevukawisesizitutekedaf.pdf
    • http://susasoft.com/upload/userfiles/files/paxiwav.pdf
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613918a5824b5---88373457025.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=smart+lock+apk
    • 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_off0000c1e6.bin
0641570a05147db9f7086bb6140a8fbc0b827e0fcc8c574a74284150d5919ee1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC1E6 17556 bytes
font_01_sfnt_off0000eef7.bin
f403a8cf5c2939db6c41d9a8c089cbc1b9f80fda86361bf8b2fd5d96575780cc
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF7 10208 bytes
font_02_sfnt_off000105ed.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x105ED 16792 bytes