Malicious PDF — malware analysis report

Static analysis result for SHA-256 776c4b03d8233ad4…

MALICIOUS

PDF

58.7 KB Created: 2020-08-22 03:09:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e589b99212031e4f60ac050704ef77f9 SHA-1: 5e81254f24b9e4c64913138821246234e9d65005 SHA-256: 776c4b03d8233ad433d011cc9eab263d1dccd92a30070b13a3f69b33e678af95
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to a link farm designed to redirect users to malicious infrastructure. The primary malicious URL identified is a redirector that appears to be part of a campaign to lure users with topics like 'yahoo answers profile search'. The ML classifier strongly indicates maliciousness, and the PDF structure suggests an attempt to disguise malicious links within a large number of seemingly benign ones.

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=yahoo+answers+profile+search
    • http://files.kcriskselectors.org/uploads/1/3/1/4/131438571/2129812.pdf
    • http://files.vandunet.com/uploads/1/3/1/8/131856108/4258465.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://cdn.shopify.com/s/files/1/0434/7042/2180/files/17154961578.pdf
    • https://cdn.shopify.com/s/files/1/0454/7146/5624/files/stepwise_regression_in_r.pdf
    • https://cdn.shopify.com/s/files/1/0434/6272/1688/files/backgammon_strategy.pdf
    • https://cdn.shopify.com/s/files/1/0440/5349/5958/files/wuxere.pdf
    • https://cdn.shopify.com/s/files/1/0438/5210/3842/files/97824705294.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/pedarivorenali.pdf
    • https://cdn.shopify.com/s/files/1/0434/5187/5481/files/visifubumoxumopegowad.pdf
    • https://cdn.shopify.com/s/files/1/0434/6534/3141/files/53701791311.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00008d4b.bin
d0b4a05715f71ad27f7ab7c4c192243f6b28333a521a327bc9c311a43d90202e
pdf-font-stream PDF embedded font (sfnt) at offset 0x8D4B 3796 bytes
font_01_sfnt_off00009ac1.bin
f8882f77f20e119fd9785d9f93434d359d406154b27a1ebb5574f4bbfc650aef
pdf-font-stream PDF embedded font (sfnt) at offset 0x9AC1 4864 bytes
font_02_sfnt_off0000ab45.bin
d68b63ef49fca9c9c6d0af63e268755e9f0ce4731734ed5f3b8459f3884ab887
pdf-font-stream PDF embedded font (sfnt) at offset 0xAB45 10756 bytes
font_03_sfnt_off0000cfe2.bin
7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71
pdf-font-stream PDF embedded font (sfnt) at offset 0xCFE2 4324 bytes