Malicious PDF — malware analysis report

Static analysis result for SHA-256 8451afeb27a245dd…

MALICIOUS

PDF

104.5 KB Created: 2020-07-30 10:22:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 55d29b1f518fac4e0d2dea25cfc441c0 SHA-1: 25c0516a415d852cd9edf240349425f79f44418c SHA-256: 8451afeb27a245ddc7d8ba93f03d7064323920d8e815bd71d56bac791816e9a3
154 Risk Score

Malware Insights

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

The PDF contains a critical heuristic indicating it links to known malicious redirector infrastructure. Additionally, it features a large number of external PDF links, suggesting an attempt at SEO poisoning or a link farm for distributing malicious content. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, but the embedded URLs are the primary indicators of 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=fibras+textiles+sinteticas+pdf
    • http://files.lilydermis.com/uploads/1/3/0/7/130775465/rewuki.pdf
    • http://files.blueabstractart.com/uploads/1/3/1/8/131872178/76448.pdf
    • http://files.woodsport.com/uploads/1/3/0/7/130739696/powebije.pdf
    • http://files.jelanaduncangolf.com/uploads/1/3/2/8/132815960/nelozabi.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/5552/9640/files/dawujejugisivuzibikixasox.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/74535711799.pdf
    • https://cdn.shopify.com/s/files/1/0429/8106/4853/files/10716438244.pdf
    • https://cdn.shopify.com/s/files/1/0434/8562/6528/files/70063558515.pdf
    • https://cdn.shopify.com/s/files/1/0430/8451/3440/files/95121142914.pdf
    • https://cdn.shopify.com/s/files/1/0431/9825/1165/files/jiwukowewesizokuf.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/lekutaxawiwasutoxojopelor.pdf
    • https://cdn.shopify.com/s/files/1/0437/1863/9771/files/fogosuxugavizato.pdf
    • https://cdn.shopify.com/s/files/1/0433/7431/3621/files/68914053412.pdf
    • https://cdn.shopify.com/s/files/1/0430/4361/8965/files/40109554584.pdf
    • https://cdn.shopify.com/s/files/1/0432/0821/2638/files/49417570696.pdf
    • https://cdn.shopify.com/s/files/1/0431/4519/9777/files/wufamofodikefebozufumob.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_off00015659.bin
f565a4f75cd3f359aa93f126877b34c9e0bb5c36d05de4da3a0b2e513c419ab1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15659 4988 bytes
font_01_sfnt_off00016750.bin
ae4ac166d829092c91b5a9a721317dd6148cc877d483c28092ec4ebf9b48d0fb
pdf-font-stream PDF embedded font (sfnt) at offset 0x16750 14084 bytes