Malicious PDF — malware analysis report

Static analysis result for SHA-256 81249a02e8dc15cf…

MALICIOUS

PDF

42.7 KB Created: 2020-08-12 02:20:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0ce971bf6e9e368d697363aad94cc7b1 SHA-1: a28708d7c3eb71044b7f042ea4b6e9e8356a825e SHA-256: 81249a02e8dc15cf821a8cd3941e7513a2715a791de59e1186961f8603ee1ed8
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, with one heuristic specifically identifying it as a PDF link farm. The primary malicious URL, 'https://ttraff.cc/pify?keyword=das+aleph+borges+pdf', is flagged as a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains URLs that suggest a lure or redirection mechanism.

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=das+aleph+borges+pdf
    • http://rabawiv.yoonho-kim.com/uploads/1/3/1/3/131379552/0f5a8ef75dc.pdf
    • http://sunalafom.rileymeadowsstable.com/uploads/1/3/1/0/131070872/1881071.pdf
    • http://files.get2knowisi.org/uploads/1/3/0/8/130814586/9463572.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/8150/5695/files/bacterial_diseases_in_cattle.pdf
    • https://cdn.shopify.com/s/files/1/0435/6925/0463/files/79020026646.pdf
    • https://cdn.shopify.com/s/files/1/0436/8993/5002/files/greenhouse_gases.pdf
    • https://cdn.shopify.com/s/files/1/0434/7192/9496/files/9742439840.pdf
    • https://cdn.shopify.com/s/files/1/0434/9899/5864/files/77853787241.pdf
    • https://cdn.shopify.com/s/files/1/0433/4374/1083/files/pabokezonaxubomedidekos.pdf
    • https://cdn.shopify.com/s/files/1/0431/5054/0964/files/14718749099.pdf
    • https://cdn.shopify.com/s/files/1/0434/6881/6544/files/kelof.pdf
    • https://cdn.shopify.com/s/files/1/0427/4746/1788/files/kibudalobo.pdf
    • https://cdn.shopify.com/s/files/1/0432/2154/9217/files/biological_oxygen_demand_test_procedure.pdf
    • https://cdn.shopify.com/s/files/1/0437/1991/7717/files/before_we_were_yours_online.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/tuwaz.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006591.bin
3a6feb26f03eb65ce1dbd34bb453cdfc49eace07c0d494a49e60fdb4698bcec2
pdf-font-stream PDF embedded font (sfnt) at offset 0x6591 5444 bytes
font_01_sfnt_off00007807.bin
5aaa508f05770b74aa314649225a8170afdfa021769d52af9b72928c25f726e6
pdf-font-stream PDF embedded font (sfnt) at offset 0x7807 11136 bytes