Malicious PDF — malware analysis report

Static analysis result for SHA-256 65cf641e30c5feb6…

MALICIOUS

PDF

43.9 KB Created: 2020-08-14 03:42:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f832307218bf6940ff5a03a84a863684 SHA-1: 27de0ed23e5119cf3080783230fdec5c270bd2c5 SHA-256: 65cf641e30c5feb603cf9a997198b3f3e12cdffd9c6366d6d66c1d2354fd0368
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to redirector infrastructure or potentially malicious domains, disguised as IELTS study materials. The ML classifier strongly indicated maliciousness, and the PDF_MALICIOUS_REDIRECTOR_LINK heuristic confirms the presence of links to known malicious sites. The document body itself contains the primary malicious URL and a list of other URLs, suggesting a link farm or redirection scheme.

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=ielts+general+reading+sample+questions+and+answers
    • http://files.thelaughingsole.org.uk/uploads/1/3/0/9/130969384/rolakamofaleva-nikozew.pdf
    • http://files.larryssportsexchange.com/uploads/1/3/0/8/130874128/folerezome.pdf
    • http://files.delawaremusic.net/uploads/1/3/1/4/131437778/502d98e3f9fa38d.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://cdn.shopify.com/s/files/1/0434/2421/9288/files/canon_6d_mark_2_manual.pdf
    • https://cdn.shopify.com/s/files/1/0440/4481/2438/files/57240799455.pdf
    • https://cdn.shopify.com/s/files/1/0429/8869/9802/files/69143305308.pdf
    • https://cdn.shopify.com/s/files/1/0428/2561/3475/files/wusejexuxesavemodor.pdf
    • https://cdn.shopify.com/s/files/1/0427/4018/7303/files/90071466363.pdf
    • https://cdn.shopify.com/s/files/1/0440/9013/0584/files/wobidevevoset.pdf
    • https://cdn.shopify.com/s/files/1/0438/8811/5867/files/zumajudipujafamipisog.pdf
    • https://cdn.shopify.com/s/files/1/0431/7783/6702/files/lesukifajuku.pdf
    • https://cdn.shopify.com/s/files/1/0431/4651/0504/files/gibadupiximi.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000060e2.bin
ef8bef9cf6ad66c7b6cfe813c8ee6c5e4c8163ceefa05644e3e6cea44bddb12e
pdf-font-stream PDF embedded font (sfnt) at offset 0x60E2 5316 bytes
font_01_sfnt_off000072db.bin
4e94aefc158fe84b24d4ad66705f1417f599f6a3bf518c9fb784ab1ae90d18c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x72DB 9848 bytes
font_02_sfnt_off00009470.bin
ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x9470 4324 bytes