Malicious PDF — malware analysis report

Static analysis result for SHA-256 f55bc4f48e4a5aab…

MALICIOUS

PDF

69.3 KB Created: 2020-08-14 06:04:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cb887be2a951865de031dfb1c4f6ea13 SHA-1: 6e50f5c97503ac8beab5f340d979a1b62587d4c4 SHA-256: f55bc4f48e4a5aab9509b9365b963be86a92be49decafac19889822df93ba133
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.ru/wb?keyword=cours%20de%20droit%20civil%20gabonais%20pdf'. This indicates the document's primary purpose is to redirect users to a potentially harmful site. The presence of a large number of external PDF links further supports a link farm or redirection strategy. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://ttraff.ru/wb?keyword=cours%20de%20droit%20civil%20gabonais%20pdf
    • http://pukulasiv.yousaidwhatgod.com/uploads/1/3/2/6/132695903/nejimugunekawutewali.pdf
    • http://gigawe.weaversofeternity.com/uploads/1/3/1/6/131637016/5167637.pdf
    • http://files.leandremeldener.com/uploads/1/3/1/4/131407357/zelinomuz.pdf
    • http://files.cheetahfloorsystems.com/uploads/1/3/2/8/132815298/db405439a4.pdf
    • http://files.paulsimpson.org/uploads/1/3/0/7/130775354/wevonur-zudexolaxo-jirigepal-dopupikofivafow.pdf
    • https://cdn.shopify.com/s/files/1/0432/9550/6592/files/54338127508.pdf
    • https://cdn.shopify.com/s/files/1/0431/4857/4884/files/zurobef.pdf
    • https://cdn.shopify.com/s/files/1/0434/7409/2196/files/9769672361.pdf
    • https://cdn.shopify.com/s/files/1/0432/2613/6731/files/rajupemef.pdf
    • https://cdn.shopify.com/s/files/1/0429/8860/1503/files/bisowogu.pdf
    • https://cdn.shopify.com/s/files/1/0430/4489/6925/files/xupudolinamizitoletesev.pdf
    • https://cdn.shopify.com/s/files/1/0433/7955/6504/files/33637648378.pdf
    • https://cdn.shopify.com/s/files/1/0431/3009/3728/files/suname.pdf
    • https://cdn.shopify.com/s/files/1/0437/1005/4554/files/96456083650.pdf
    • https://cdn.shopify.com/s/files/1/0430/7235/6513/files/guia_de_medicina_ambulatorial_e_hospitalar_unifesp_nutrio.pdf
    • https://cdn.shopify.com/s/files/1/0436/4160/2208/files/dotatar.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ceca.bin
3e8165dde3b51e77b78cdafc9086cc7d422b7e908ab33910ebe9122cb348bf46
pdf-font-stream PDF embedded font (sfnt) at offset 0xCECA 5428 bytes
font_01_sfnt_off0000e152.bin
c6450faf34e76ecee5314b2a019dd592885db5c3787d8bb63d5a06c73029b444
pdf-font-stream PDF embedded font (sfnt) at offset 0xE152 12376 bytes