Malicious PDF — malware analysis report

Static analysis result for SHA-256 923ea5b0c798bc4c…

MALICIOUS

PDF

42.5 KB Created: 2020-08-07 19:23:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2cd414c6f6520be3bc5985c90826425b SHA-1: aa586bb60d7ebf9ae46ec798087385d06967b104 SHA-256: 923ea5b0c798bc4c8b96e10f1b1cbf12e87f516ef8b9cbf67f456ffcc81b4f2e
152 Risk Score

Malware Insights

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

The PDF contains numerous links, including one pointing to a known malicious redirector at 'https://ttraff.cc/pify?keyword=beginner+english+questions+pdf'. The ML classifier strongly indicated maliciousness, and the presence of a link farm suggests an attempt to distribute malicious content or engage in SEO abuse. The document body, though heavily obfuscated, contains the same URL, reinforcing the malicious intent.

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.cc/pify?keyword=beginner+english+questions+pdf
    • http://files.bamfm.org/uploads/1/3/1/4/131437362/wexarepu-samikoxuf-nusebexiwiwetu-jixovup.pdf
    • http://rarixoro.thetaoofrudy.net/uploads/1/3/1/8/131856772/sazux.pdf
    • http://fivif.apahcare.com/uploads/1/3/2/8/132816066/fojevodat.pdf
    • https://cdn.shopify.com/s/files/1/0429/9204/2137/files/6467891131.pdf
    • https://cdn.shopify.com/s/files/1/0430/7927/0561/files/uninstall_github_desktop.pdf
    • https://cdn.shopify.com/s/files/1/0437/3279/5541/files/bamuzakene.pdf
    • https://cdn.shopify.com/s/files/1/0430/4479/8613/files/98025816750.pdf
    • https://cdn.shopify.com/s/files/1/0435/5312/8612/files/80500271122.pdf
    • https://cdn.shopify.com/s/files/1/0430/4768/2201/files/modawaki.pdf
    • https://cdn.shopify.com/s/files/1/0429/8558/6841/files/77061960327.pdf
    • https://cdn.shopify.com/s/files/1/0429/2067/3433/files/nuroxajezikeso.pdf
    • https://cdn.shopify.com/s/files/1/0432/6454/0835/files/vorikularo.pdf
    • https://cdn.shopify.com/s/files/1/0432/5310/4790/files/657_220-_1619.pdf
    • https://cdn.shopify.com/s/files/1/0434/8048/1954/files/capacitor_calculation.pdf
    • https://cdn.shopify.com/s/files/1/0432/5038/5051/files/vorediti.pdf
    • https://cdn.shopify.com/s/files/1/0428/4517/5971/files/nuserarezezupiwizozosu.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_off00006940.bin
8c4a33d427e62212692497f4cb7d2d268f04dda7635bd37799ee5c837ad12dfe
pdf-font-stream PDF embedded font (sfnt) at offset 0x6940 5268 bytes
font_01_sfnt_off00007b24.bin
03a5ff599f74ec4530ebd6c5d4cadfb9d2f560a88d6e9cd2ee605ff229a09000
pdf-font-stream PDF embedded font (sfnt) at offset 0x7B24 10020 bytes