Malicious PDF — malware analysis report

Static analysis result for SHA-256 26e13f7fd0d87d8b…

MALICIOUS

PDF

40.2 KB Created: 2020-08-15 17:36:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e5391a7d82e7c268500bc4ba8577ae51 SHA-1: 76dffc8c9b31a296abf1d3cf45821106ec0305a9 SHA-256: 26e13f7fd0d87d8bf0b4f995aadc7f29035876c914c1b70990e90f59109887af
154 Risk Score

Malware Insights

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

The PDF contains embedded links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'Linux shell script guide pdf' and the malicious URL, suggesting a lure to trick users into downloading or accessing harmful content. The presence of a large number of external PDF links also indicates a link farm strategy, likely for SEO manipulation or to distribute malicious payloads.

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/wb?keyword=linux%20shell%20script%20guide%20pdf
    • http://files.educatorsforsocialjustice.org/uploads/1/3/1/6/131606890/kifiwip.pdf
    • https://cdn.shopify.com/s/files/1/0429/4891/9459/files/dokozutuxidawojetajava.pdf
    • https://cdn.shopify.com/s/files/1/0436/5431/6197/files/99314392991.pdf
    • https://cdn.shopify.com/s/files/1/0439/0505/6920/files/latopag.pdf
    • https://cdn.shopify.com/s/files/1/0434/7786/0516/files/kulomikakuzatu.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/datumaf.pdf
    • https://cdn.shopify.com/s/files/1/0436/4340/4441/files/datafidejorirolitexewur.pdf
    • https://cdn.shopify.com/s/files/1/0433/2093/4558/files/bloons_td_6_free_for_pc.pdf
    • https://cdn.shopify.com/s/files/1/0430/4008/0021/files/additives_for_lubricants.pdf
    • https://cdn.shopify.com/s/files/1/0430/5915/1009/files/biggest_city_in_mississippi.pdf
    • https://cdn.shopify.com/s/files/1/0435/7367/4142/files/juriz.pdf
    • https://cdn.shopify.com/s/files/1/0427/8799/5807/files/dell_poweredge_r440_server.pdf
    • https://cdn.shopify.com/s/files/1/0430/4227/5479/files/wiguzawoxanejuwevuleto.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_off00006094.bin
fca41c0a7945c17813ed500d9984d71e960d3bc5bed347474f53fccbb4fd2e03
pdf-font-stream PDF embedded font (sfnt) at offset 0x6094 5216 bytes
font_01_sfnt_off00007251.bin
bfd9463e7adba19a8cfdfa5ca7fcae36690a303124f0276d3d18b7b69cd08c03
pdf-font-stream PDF embedded font (sfnt) at offset 0x7251 9928 bytes