Malicious PDF — malware analysis report

Static analysis result for SHA-256 b26756984443eb5c…

MALICIOUS

PDF

59.2 KB Created: 2020-09-01 08:55:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d5be4d6833f45fc1253d35cafa5a165c SHA-1: aca68d9cf694833394c2b83e947a59d225a0c89f SHA-256: b26756984443eb5c4e5eca59c36a824b70dfe06e71d3419b27c5b81a1fbdf498
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious due to a critical heuristic identifying a link to known malicious redirector infrastructure. Additionally, another critical heuristic detected a large number of external PDF links, suggesting a link farm or SEO abuse. The ML classifier also strongly indicated maliciousness. The primary IOC is the redirector URL, which is likely the initial point of contact for a phishing or malware delivery scheme.

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/wix?keyword=aashiqui+audio+songs++telugu
    • https://static.usrfiles.com/ugd/3ceeb9_5dca8db4718348ae80971adf790ab513.pdf
    • https://static.usrfiles.com/ugd/764aaa_66f3b7b673294b5fb464f09f3d6b2c37.pdf
    • https://static.usrfiles.com/ugd/a107db_c9dd058e2058497e9db9a7245b63309f.pdf
    • https://static.usrfiles.com/ugd/fd30ac_6e9a4752f53943b2aefa2ee1b11a17f8.pdf
    • https://static.usrfiles.com/ugd/3e9e83_c374796b56fe4f32805ab851cbaf6acc.pdf
    • https://static.usrfiles.com/ugd/b8c837_8e1b253cbb1f4a0d8a0cbfac212b163b.pdf
    • https://static.usrfiles.com/ugd/bf650e_b84528d4d2cb4d96bf94768a2d7e9496.pdf
    • https://static.usrfiles.com/ugd/6cfc61_bc2810ad9cc14286b38725e7c4b85e5c.pdf
    • https://static.usrfiles.com/ugd/47b1e8_3d4a259a33c44446b2110ca73bcec704.pdf
    • https://static.usrfiles.com/ugd/aa14a9_eaa86efbf1974765baff79a04d313758.pdf
    • https://static.usrfiles.com/ugd/895bef_acb9a2efb98148e2a4377f43c1e48664.pdf
    • https://static.usrfiles.com/ugd/b8c837_549c9876e97844ce934c9dd34441b7b0.pdf
    • https://cdn.shopify.com/s/files/1/0438/2185/8973/files/31016306906.pdf
    • https://cdn.shopify.com/s/files/1/0431/8029/4306/files/wiridirulisij.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00009530.bin
1451ce33fbaf974e37cd71ae3f2ab7a7326816e8b40b1c5277e95682df5f5bf8
pdf-font-stream PDF embedded font (sfnt) at offset 0x9530 5104 bytes
font_01_sfnt_off0000a67f.bin
98907dc8a35dbde263a485d8f9b47566468d97c755e957fb72f80caf3767aa32
pdf-font-stream PDF embedded font (sfnt) at offset 0xA67F 10400 bytes
font_02_sfnt_off0000ca5f.bin
e296a61d2d303e35be9e1a35631556663d2780498efa7e8f3867bf557f172fe6
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA5F 16164 bytes