Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2c156e0139a63d8…

MALICIOUS

PDF

41.1 KB Created: 2020-08-18 23:18:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 24365a37a271f69e8eadfb6fc713e7bb SHA-1: 876bcbf892d6c7d497a3a362cf20452a162a5ef0 SHA-256: a2c156e0139a63d82ffa6aa01c006884445345ee4d4c6d5d350aa5b71b3fbdd6
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to Shopify domains, but one critical link directs to a known malicious redirector at 'ttraff.com'. The document body, though heavily obfuscated, contains text related to 'Acca f5 performance management syllabus' and the malicious URL, suggesting a lure. The ML classifier strongly flagged this PDF as malicious, and the presence of a redirector link indicates an attempt to lead the user to a malicious site.

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.com/pify?keyword=acca+f5+performance+management+syllabus
    • http://nasiwu.chrisgamecasting.com/uploads/1/3/0/7/130739017/d8858a.pdf
    • http://files.invictahealthcare.net/uploads/1/3/0/7/130776646/fesofijijol.pdf
    • https://cdn.shopify.com/s/files/1/0435/1649/3976/files/veditavejumapuvap.pdf
    • https://cdn.shopify.com/s/files/1/0439/3621/9291/files/shikomita_glory_days.pdf
    • https://cdn.shopify.com/s/files/1/0441/3744/7576/files/officer_buckle_and_gloria.pdf
    • https://cdn.shopify.com/s/files/1/0431/0827/0244/files/laxij.pdf
    • https://cdn.shopify.com/s/files/1/0432/7922/0891/files/tofewofawepegi.pdf
    • https://cdn.shopify.com/s/files/1/0428/1604/5222/files/19287525486.pdf
    • https://cdn.shopify.com/s/files/1/0431/4575/6833/files/jilanugelekemetawodumobod.pdf
    • https://cdn.shopify.com/s/files/1/0434/2779/1009/files/3160658751.pdf
    • https://cdn.shopify.com/s/files/1/0429/7005/4805/files/93485546433.pdf
    • https://cdn.shopify.com/s/files/1/0432/4818/9603/files/bacteriophage_proteins.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_off00006175.bin
e11637b635ec6dd95846cea1994ad42affb5df5248da92c1b361b687e27ae788
pdf-font-stream PDF embedded font (sfnt) at offset 0x6175 5692 bytes
font_01_sfnt_off000074c1.bin
16fbcd59ed0f6dfdffbcd30ebdfc7d571d35346b2347c222b4c5c9bac2459c2d
pdf-font-stream PDF embedded font (sfnt) at offset 0x74C1 10256 bytes