Malicious PDF — malware analysis report

Static analysis result for SHA-256 552d953edbfbf2b4…

MALICIOUS

PDF

41.8 KB Created: 2020-08-14 21:00:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 345be09e67cab334cc64cb724eb7b88b SHA-1: 5fcec9a2d30d41884e60e87f8e22dfebfc7c576e SHA-256: 552d953edbfbf2b47e41749cf32e7a30c7050f8755c1aa81cc15dc2cd564cc04
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a critical heuristic firing for a malicious redirector link, which is the primary attack vector. It also exhibits characteristics of a link farm, with numerous embedded URLs pointing to external PDF files, likely for SEO manipulation to lure victims. The ML classifier strongly supports the malicious nature of this PDF. The embedded URLs are used to redirect users to potentially 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.cc/wb?keyword=hindu%20holy%20book%20ramayana%20in%20urdu%20pdf
    • http://files.berkshireheros.org/uploads/1/3/0/7/130775320/gujanulifuz.pdf
    • http://files.mammologix.us/uploads/1/3/0/7/130775205/4868771.pdf
    • https://cdn.shopify.com/s/files/1/0433/5465/2822/files/espaa_en_africa_subsahariana.pdf
    • https://cdn.shopify.com/s/files/1/0432/1656/8482/files/61310472537.pdf
    • https://cdn.shopify.com/s/files/1/0446/0707/8564/files/9033044494.pdf
    • https://cdn.shopify.com/s/files/1/0431/7259/3832/files/87677979560.pdf
    • https://cdn.shopify.com/s/files/1/0436/8000/6294/files/josijegipuminoxubevuv.pdf
    • https://cdn.shopify.com/s/files/1/0430/8946/1402/files/fivefeberesiburugoveki.pdf
    • https://cdn.shopify.com/s/files/1/0432/7079/9510/files/85373864390.pdf
    • https://cdn.shopify.com/s/files/1/0435/4218/4095/files/ximunevepujikupeko.pdf
    • https://cdn.shopify.com/s/files/1/0434/0809/7445/files/lowegagevapuwojek.pdf
    • https://cdn.shopify.com/s/files/1/0430/8788/8535/files/fixinosev.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005b5b.bin
0250cf1140017444b38b1d0c9df5f31b4b22131e349acee8689e24e029f87f86
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B5B 5368 bytes
font_01_sfnt_off00006d6b.bin
73983ccd477f0e4c07634362c0f9f13a23cea415a26bff37f7f125d59a681190
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D6B 1936 bytes
font_02_sfnt_off000076ae.bin
2ae260a30cc88fb3c99111aec8e1e1b930a8b0c9e554ff388d6e88f437246a7e
pdf-font-stream PDF embedded font (sfnt) at offset 0x76AE 10396 bytes