Malicious PDF — malware analysis report

Static analysis result for SHA-256 83c5163dfc076eb7…

MALICIOUS

PDF

45.6 KB Created: 2020-09-11 07:53:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 558558449420659038a5cface963db36 SHA-1: 725070ace1e71ec084ed7ad88c3b8e54d3a84d28 SHA-256: 83c5163dfc076eb77e79197d0d885a7d83c7c749c939019752dd8f7fada242b6
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one identified as a malicious redirector. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external PDF links, suggesting an attempt to manipulate search engine results or distribute content. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics point towards a phishing or content-luring attack vector, likely initiated via spearphishing.

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.me/wix?keyword=best+preloaded+android+tv+box+uk
    • http://files.wischandjackson.com/uploads/1/3/1/4/131438784/jirebe-paxowenatarubi-xoxegeridokuke.pdf
    • http://files.swirlybugz.com/uploads/1/3/0/7/130776408/segipidaku.pdf
    • http://files.americanacademicconnections.com/uploads/1/3/0/7/130776745/noniro_masisodi.pdf
    • http://files.greatharvestclackamas.com/uploads/1/3/1/3/131383657/8429704.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_21b5a5a532714f12850f8b1957d32f77.pdf
    • https://static.usrfiles.com/ugd/4ca7f5_d759baae3c58454eaebc1df279b29b11.pdf
    • https://static.usrfiles.com/ugd/8c2e83_b3d4f8e5b19b4548a6495379c88f978d.pdf
    • https://static.usrfiles.com/ugd/b8c837_11de0c5dc2014f0196e3ad40bd25b310.pdf
    • https://static.usrfiles.com/ugd/0cd3a8_86b623b9a45f43989a6dcacc61245871.pdf
    • https://static.usrfiles.com/ugd/771ea4_57b8368972174c9999ab66b04ab7de2f.pdf
    • https://static.usrfiles.com/ugd/739437_109814964d9d40fe8309006e46101d09.pdf
    • https://cdn.shopify.com/s/files/1/0433/5858/4986/files/autocad_2020_tutorial_free.pdf
    • https://cdn.shopify.com/s/files/1/0428/4504/4892/files/simuraraguliz.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_off0000737e.bin
9e497f799552ceb055735ac12d8efef1d94632ed0144a195c00d5269685c971a
pdf-font-stream PDF embedded font (sfnt) at offset 0x737E 5336 bytes
font_01_sfnt_off000085b1.bin
28d4de6ae2cf0eeee527d611b0c8debadcafb63225c9768ddd5b520fd9043051
pdf-font-stream PDF embedded font (sfnt) at offset 0x85B1 10412 bytes