Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d9798d802bf57b3…

MALICIOUS

PDF

56.4 KB Created: 2020-08-11 17:29:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6c7fc4d282794f1d2108a163e10af25c SHA-1: 96e59bc6db4962d58bec06f10eaec609bc33019b SHA-256: 6d9798d802bf57b30d63935a21d99db3265feae6e01c6eb91f756c71984609d4
154 Risk Score

Malware Insights

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

The PDF document contains a lure promising free downloads, which redirects to a known malicious redirector URL. The document body itself is heavily obfuscated but contains multiple links to external PDF files, likely part of a link farm to improve SEO for malicious content. The ML classifier strongly indicated maliciousness, and the presence of a redirector link confirms a malicious intent to lead the user to harmful content.

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=small+stories+pdf+free+download
    • http://files.ashcandesign.com/uploads/1/3/0/8/130873851/9dc7c4c2d5ca4.pdf
    • http://dazik.tandem-cyber-solutions.com/uploads/1/3/0/8/130873995/fc5e7776b043c15.pdf
    • http://files.cazpurrbengalcats.com/uploads/1/3/2/8/132814073/vatosetejo.pdf
    • http://files.southendrising.com/uploads/1/3/1/3/131380438/3ed3f.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0431/4929/5776/files/degotumikotimimena.pdf
    • https://cdn.shopify.com/s/files/1/0434/7222/4421/files/29104431094.pdf
    • https://cdn.shopify.com/s/files/1/0428/1312/8867/files/lodaj.pdf
    • https://cdn.shopify.com/s/files/1/0433/4062/8120/files/27392789372.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/wexidemunuviviradepinitim.pdf
    • https://cdn.shopify.com/s/files/1/0430/9454/0452/files/95372857848.pdf
    • https://cdn.shopify.com/s/files/1/0428/5746/3964/files/daxivagunalotit.pdf
    • https://cdn.shopify.com/s/files/1/0431/5339/1765/files/si_joint_dysfunction.pdf
    • https://cdn.shopify.com/s/files/1/0438/5102/2501/files/rewamogitiluregapi.pdf
    • https://cdn.shopify.com/s/files/1/0429/9476/1877/files/1519859487.pdf
    • https://cdn.shopify.com/s/files/1/0434/7278/1478/files/demuzepidak.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_off00009761.bin
f149b98b62f11b87446c728eccf2cd67ad4b3a3488aa577c5156be428f6e404b
pdf-font-stream PDF embedded font (sfnt) at offset 0x9761 5380 bytes
font_01_sfnt_off0000a9a0.bin
e1067c7388231901200aa47c24660c9f07a0d4579c2605896f450957fe43c49c
pdf-font-stream PDF embedded font (sfnt) at offset 0xA9A0 13700 bytes