Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f79b9bdb139b282…

MALICIOUS

PDF

45.3 KB Created: 2020-08-14 01:46:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3938237c4583842766c4d6512773b146 SHA-1: 4d8f0e3d850ddb1f5e29adaee6e3c273ec3c31cc SHA-256: 4f79b9bdb139b282d8b9e4509f25a561c1bfbefd8f02059138fc887b908cf019
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one specifically identified as a known malicious redirector. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass of external PDF links, suggesting a link farm or distribution mechanism. The ML classifier strongly supports the malicious nature of this PDF. The primary attack pattern involves leveraging these links for malicious redirection or content distribution.

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/pify?keyword=female+red+deer+crossword+answer
    • http://files.megtinsleymft.com/uploads/1/3/1/6/131607467/misejasuno_movaza_situmi_jaguwila.pdf
    • http://files.2ndcongregationalchurchvt.org/uploads/1/3/1/4/131406715/8d0796.pdf
    • http://files.whitstablemusicsociety.org.uk/uploads/1/3/1/4/131409128/xesuma_radisomuruz.pdf
    • https://cdn.shopify.com/s/files/1/0434/5099/0753/files/demand_driven_material_requirements_planning.pdf
    • https://cdn.shopify.com/s/files/1/0427/9618/7815/files/xijefo.pdf
    • https://cdn.shopify.com/s/files/1/0432/3550/8387/files/camara_de_comercio_internacional.pdf
    • https://cdn.shopify.com/s/files/1/0434/0659/0106/files/46094684455.pdf
    • https://cdn.shopify.com/s/files/1/0437/2063/8632/files/bujudeziloxanenigupur.pdf
    • https://cdn.shopify.com/s/files/1/0432/2020/5726/files/2212844159.pdf
    • https://cdn.shopify.com/s/files/1/0431/6394/3067/files/bootstrap_4_cdn_template.pdf
    • https://cdn.shopify.com/s/files/1/0430/4447/0945/files/zaxakekikeraroxitixetuk.pdf
    • https://cdn.shopify.com/s/files/1/0448/2033/2705/files/zinovukulibew.pdf
    • https://cdn.shopify.com/s/files/1/0431/6600/7445/files/leninafipeganizoweg.pdf
    • https://cdn.shopify.com/s/files/1/0428/5690/6918/files/69842939783.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_off0000746c.bin
22b5ffa0ea730d0cef7990ec27581c574425af104c6b1abf17e2592d5583a061
pdf-font-stream PDF embedded font (sfnt) at offset 0x746C 5132 bytes
font_01_sfnt_off000085d5.bin
09fce240b5a52ee27785cddaf694a2d186c6c5afc81ac3c3a5389361acb9f4d8
pdf-font-stream PDF embedded font (sfnt) at offset 0x85D5 10104 bytes