Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c802371ad368996…

MALICIOUS

PDF

41.1 KB Created: 2020-09-04 19:04:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1b137b1c9b39c8f5f88d053d494c302b SHA-1: fef876344b179729f16aea8143b4927a159d2360 SHA-256: 4c802371ad36899602d141db633851db73d5b72b667720e53077bfdb15765cbf
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 pointing to 'https://ttraff.me/wix?keyword=paytm+wallet+app++for+android'. This indicates the document's primary purpose is to redirect the user to a potentially harmful external site. The presence of a large number of other PDF links, many hosted on 'static.usrfiles.com', suggests a link farm or SEO poisoning tactic to obscure the malicious redirector. The ML classifier also strongly flagged this PDF as malicious.

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=paytm+wallet+app++for+android
    • https://static.usrfiles.com/ugd/ea9bdf_301cdecd071f4d159b503d1fc70cec6f.pdf
    • https://static.usrfiles.com/ugd/140efa_b195bfdfd7c3414387f76a68e17699c1.pdf
    • https://static.usrfiles.com/ugd/cbdbb6_3038a5cb55764ebe9fbff21a1f589aa9.pdf
    • https://static.usrfiles.com/ugd/b8c837_6fa6dc405ed3443ebdf37def48f500db.pdf
    • https://static.usrfiles.com/ugd/9904c2_61330c181dcb4866b88998e4d2e6d90e.pdf
    • https://static.usrfiles.com/ugd/fac845_b005f22f5e9b4bad9ee11cbbb95fba7f.pdf
    • https://static.usrfiles.com/ugd/3eed2b_d408abdbd9d747828983fde2b6445d6d.pdf
    • https://static.usrfiles.com/ugd/aaaf79_8aac97b1d84c45b5933275cfe241da8c.pdf
    • https://static.usrfiles.com/ugd/0251f0_8b7b8013cd2b43ee8aec937fac0750a4.pdf
    • https://static.usrfiles.com/ugd/b8c837_686d7e1507834feaa6062da4f1634f69.pdf
    • https://static.usrfiles.com/ugd/c1c462_913f266858e84cc4b81f5ac9ee36c103.pdf
    • https://cdn.shopify.com/s/files/1/0431/7007/0690/files/dubimawajowidisavukabode.pdf
    • https://cdn.shopify.com/s/files/1/0434/4912/2983/files/45905295359.pdf
    • https://cdn.shopify.com/s/files/1/0451/2360/0538/files/556199007.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_off000063e2.bin
08b75ee19237e9262a7997a1b87acca6d3189420666a0ab8e6862d2194176c97
pdf-font-stream PDF embedded font (sfnt) at offset 0x63E2 5204 bytes
font_01_sfnt_off00007599.bin
24f3fa5283a047f762665bb39e62127a844a274b31b9cada21cf26f2697c716a
pdf-font-stream PDF embedded font (sfnt) at offset 0x7599 9952 bytes