Malicious PDF — malware analysis report

Static analysis result for SHA-256 8849c2b33eefb54f…

MALICIOUS

PDF

96.1 KB Created: 2021-09-19 01:05:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 05fa48b80ac5828289f9f135c77cb74f SHA-1: 45de41737126e50f0cf98e47c7a3f90ae6b0ae4f SHA-256: 8849c2b33eefb54f796f0a3b3b92ad4b7e7259a5ea6dda698d4cc49815790eae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 http://agrostroi-proekt.ru/ckfinder/userfiles/files/momumifagivite.pdf In PDF document text
    • https://www.funes.gob.ar/ckfinder/userfiles/files/92586941186.pdfIn PDF document text
    • http://bridgeonlaw.com/filespath/files/20210915194433.pdfIn PDF document text
    • http://zhouzhuank.com/v15/Upload/file/202199115306042.pdfIn PDF document text
    • https://quanghuydulich.vn/img_duhoc/files/53223419081.pdfIn PDF document text
    • https://tutorlookup.com/ckeditor/ckfinder/userfiles/files/ruwisizararuveditilokuki.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131bbff09aad---wunesaxupenizovurug.pdfIn PDF document text
    • http://cybernet.asia/UserFiles/File/taguwifos.pdfIn PDF document text
    • https://maxlinder.com/admin/assets/ckfinder/userfiles/files/zorebuwazebopisobadela.pdfIn PDF document text
    • http://dooroc.com/tk/upload/file/41496408069.pdfIn PDF document text
    • http://nerezove-kuchyne.cz/UserFiles/File/xuzetatibekutat.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/70954120735.pdfIn PDF document text
    • https://csam-villepinte.org/uploads/images/file/gamanikexizawa.pdfIn PDF document text
    • http://www.museopizarra.com/ckfinder/userfiles/files/mowikobuzexewuw.pdfIn PDF document text
    • https://copperscrap.wasteequipment.net/ckfinder/userfiles/files/19486506454.pdfIn PDF document text
    • https://kolbandibileklik.com/resimler/files/tevipijomiremew.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/zujewixijigezoz.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/lafurez.pdfIn PDF document text
    • https://home-consult.lu/userfiles/files/gasitemu.pdfIn PDF document text
    • https://invest.pl/userfiles/file/18658603215.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16134ca500b659---sexenes.pdfIn PDF document text
    • https://xtrafitcoaching.com/www/images/files/talajegosoxujusanewevet.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/161422f33d423a---temogonowamusovinipoxowi.pdfIn PDF document text
    • http://kadet-ck.cz/pic/file/53098831703.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=the+diving+bell+and+the+butterfly+book+pdfPDF link annotation
    • 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_off00010e88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E88 19288 bytes
SHA-256: 35660fc158abb1b28657b4c6134c89edb7d25bcfb54981d4910e6e6f99ac2365
font_01_sfnt_off000140d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140D3 11084 bytes
SHA-256: 37c37a92096f3d0ce8da19624a3bb061c3413d7ba45f2fab62600f96400c6828
font_02_sfnt_off00015a2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A2F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1