Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2be5e113e388cca…

MALICIOUS

PDF

42.2 KB Created: 2020-08-09 13:35:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d741090696a3efe11a3598afddffd7eb SHA-1: f9fa69d3dba85d4991da9881c6a94ffd77bb9599 SHA-256: a2be5e113e388cca659d1339a8f71e872ad5ea98afd3062fdc973dd7c5e8fc68
152 Risk Score

Malware Insights

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

The PDF contains a mass of external links, many pointing to a redirector infrastructure. The primary malicious URL identified is https://ttraff.ru/pify?keyword=arithmetic+mean+and+geometric+mean+pdf. This suggests a link farm or SEO poisoning attack designed to drive traffic to malicious sites. The ML classifier strongly supports the malicious nature of this PDF.

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=arithmetic+mean+and+geometric+mean+pdf
    • http://riwapade.choralartsmusic.org/uploads/1/3/0/7/130775062/7048760.pdf
    • http://files.highaltitudevitaefitness.org/uploads/1/3/0/7/130776204/cdd069caa9a69b.pdf
    • http://files.spartanburgrepertory.com/uploads/1/3/2/6/132681836/3615501.pdf
    • https://cdn.shopify.com/s/files/1/0434/4699/3063/files/53576181001.pdf
    • https://cdn.shopify.com/s/files/1/0429/6704/0154/files/wijabelewekepurazevolujof.pdf
    • https://cdn.shopify.com/s/files/1/0431/9795/6256/files/11895266702.pdf
    • https://cdn.shopify.com/s/files/1/0431/3153/5524/files/vidoluzuse.pdf
    • https://cdn.shopify.com/s/files/1/0433/3407/4523/files/73237219845.pdf
    • https://cdn.shopify.com/s/files/1/0436/4828/6880/files/56101899774.pdf
    • https://cdn.shopify.com/s/files/1/0433/3630/2750/files/kidibewa.pdf
    • https://cdn.shopify.com/s/files/1/0432/2669/3789/files/rebomopefoned.pdf
    • https://cdn.shopify.com/s/files/1/0432/6768/6556/files/xekoxidele.pdf
    • https://cdn.shopify.com/s/files/1/0433/2650/5118/files/zujekovilan.pdf
    • https://cdn.shopify.com/s/files/1/0428/7738/6918/files/vobeperigonekaxiribefotub.pdf
    • https://cdn.shopify.com/s/files/1/0438/1576/4128/files/17517862387.pdf
    • https://cdn.shopify.com/s/files/1/0428/6241/1942/files/14351657937.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_off00006668.bin
cc13802a1692e33ec4453527f6a053b7cd3786a80423133ea15541144670bc2a
pdf-font-stream PDF embedded font (sfnt) at offset 0x6668 5348 bytes
font_01_sfnt_off00007871.bin
f8b1bec48e51a44f24fa7dbeb1b29f52c479f695ce285e82051c7e37a9195ee7
pdf-font-stream PDF embedded font (sfnt) at offset 0x7871 10316 bytes