Malicious PDF — malware analysis report

Static analysis result for SHA-256 f55ea51f76b2136f…

MALICIOUS

PDF

69.7 KB Created: 2021-10-02 09:51:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 69ae8a13af9d2b4a658e0e8113597f4b SHA-1: 9381effa5538fc485054e2a243e2f9bdcca2c0ef SHA-256: f55ea51f76b2136fb34acea990ccac83406176e7f857cb312a4a7fa1b01d7bf7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://rosanaalvarracin.com/userfiles/file/mabifubosuwu.pdf In PDF document text
    • http://ok-poland.com/userfiles/file/xedomekavomoxovezofamoju.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/3227b4692064ba1acfcda64c112eb6b6/xefediputedezevulonez.pdfIn PDF document text
    • http://drcleancenter.com/uploads/files/202109092123015672.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/21712835117.pdfIn PDF document text
    • http://waetsukai.jp/system/ckfinder/userfiles/files/fidatanoxixib.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/5a47e423a5b65f98509497dddc9a7fb0/59672671708.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/90282716466.pdfIn PDF document text
    • http://zjgjqmr.com/v15/Upload/file/20219171859554383.pdfIn PDF document text
    • http://minhphucvietnam.com/uploads/userfiles/file/49374614492.pdfIn PDF document text
    • https://nguoixunghekiev.vn/userfiles/file/tonej.pdfIn PDF document text
    • http://sntaviator.ru/ckfinder/userfiles/files/nujunitogopi.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/tk3acs1ho73h8vtmd9r7jith35/gasovubegoseloje.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16148f8a70fbdd---saramawubuvi.pdfIn PDF document text
    • http://ty-int.com/files/files/fusexalabiz.pdfIn PDF document text
    • http://axi-hohenstein.de/userfiles/file/bitudo.pdfIn PDF document text
    • https://m-isc.com/userfiles/file/fobifuvowisuxekex.pdfIn PDF document text
    • http://vibrobeton.by/pics/files/wunexojunozelolo.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/161514ee199388---40714411837.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1614492e34eef9---burezuwu.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/64229337994.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/69124860752.pdfIn PDF document text
    • https://km2804.com/ckupload/files/zovajisupamudixekabeb.pdfIn PDF document text
    • http://serdceprirody.ru/userfiles/file/43513098158.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=rocky+point+condos+for+salePDF 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_off0000b2de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2DE 14676 bytes
SHA-256: 5ef0b8562d44a2c0d97afb8bde5a2917c1038da31e665683dcfc97d636d08b29
font_01_sfnt_off0000d787.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD787 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF9E 10864 bytes
SHA-256: 745be020ac0c0518a30d46c32ef5e0bee6a9e9309121c8ccefdd6b8455c66d59