Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f758a8bb77ee1ef…

MALICIOUS

PDF

39.6 KB Created: 2020-08-14 22:46:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3630e0f6172a30dfc9ae5f5d6c743be3 SHA-1: 24a93ac27bb50409057c36a2581097e52c657ae0 SHA-256: 9f758a8bb77ee1ef5b32fc6520c8ed77c30b017a29520bd561df4e5b9fd63022
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a link farm hosted on Shopify. One of these links, https://ttraff.ru/wb?keyword=manual%20de%20bomberos%20voluntarios%20de%20guatemala, is identified as a malicious redirector. The ML classifier strongly indicates maliciousness, and the overall structure suggests a SEO poisoning or link farm attack designed to redirect users to malicious sites.

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.ru/wb?keyword=manual%20de%20bomberos%20voluntarios%20de%20guatemala
    • http://files.illinoispeoplesaction.org/uploads/1/3/1/3/131380308/votuzi.pdf
    • http://files.copernicus-training.com/uploads/1/3/0/7/130776031/dofus.pdf
    • http://files.sethled.com/uploads/1/3/1/4/131407214/bosagorobasa_kegul_tefew.pdf
    • https://cdn.shopify.com/s/files/1/0430/2651/4077/files/jurarewonipovadomap.pdf
    • https://cdn.shopify.com/s/files/1/0429/5501/4297/files/historia_de_las_bacterias.pdf
    • https://cdn.shopify.com/s/files/1/0436/7617/2441/files/baritone_ukulele_barre_chords.pdf
    • https://cdn.shopify.com/s/files/1/0440/6139/3061/files/black_voices_an_anthology_of_african_american_literature.pdf
    • https://cdn.shopify.com/s/files/1/0433/0107/7142/files/volepazaxofole.pdf
    • https://cdn.shopify.com/s/files/1/0430/8054/8503/files/jesupodinugexemegebap.pdf
    • https://cdn.shopify.com/s/files/1/0435/4605/0728/files/27747144143.pdf
    • https://cdn.shopify.com/s/files/1/0434/4093/0983/files/59833026741.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_off000058d3.bin
3d4037565be9b7b7523efc2951825601c1ef4624b93d073f4b82d7317376f86a
pdf-font-stream PDF embedded font (sfnt) at offset 0x58D3 5348 bytes
font_01_sfnt_off00006aea.bin
80566c92bce7c3823cb05ccb9cb9100661d9cfda76755f16dfd85da530dcaa55
pdf-font-stream PDF embedded font (sfnt) at offset 0x6AEA 11360 bytes