Malicious PDF — malware analysis report

Static analysis result for SHA-256 3734ef8f67eeaee5…

MALICIOUS

PDF

34.2 KB Created: 2020-08-30 19:12:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 29bd6568064da12f56e0f9b50021c0e7 SHA-1: f020b0ce753b79c4c8cf566b80bb3bf0d48c52d3 SHA-256: 3734ef8f67eeaee5a315d68fef495246d5a525370de667db5ef1e8d34ad36c79
154 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, identified as a link farm. One of these links, 'https://ttraff.com/wix?keyword=grupo+corcel+negro', points to known malicious redirector infrastructure. The ML classifier also strongly indicated maliciousness. The document body is heavily obfuscated, but the presence of the malicious URL and the link farm heuristic are sufficient to determine the attack pattern.

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/wix?keyword=grupo+corcel+negro
    • https://static.usrfiles.com/ugd/158fb9_4b8d8b17221d4d198476e4dd9f9a546d.pdf
    • https://static.usrfiles.com/ugd/0c268c_9e1e090333b24e5caeb768ad13cd104d.pdf
    • https://static.usrfiles.com/ugd/f515ca_30a0990b367c461d870da73466d19b9c.pdf
    • https://static.usrfiles.com/ugd/db1da1_a9b8787b482b4329999645949acef9be.pdf
    • https://cdn.shopify.com/s/files/1/0430/7356/8919/files/woods_digital_timer_49556_manual.pdf
    • https://cdn.shopify.com/s/files/1/0437/4259/3189/files/59119027961.pdf
    • https://cdn.shopify.com/s/files/1/0430/7219/2669/files/kuxogovo.pdf
    • https://cdn.shopify.com/s/files/1/0433/0877/7637/files/articulo_de_opinion_sobre_la_tecnologia.pdf
    • https://cdn.shopify.com/s/files/1/0429/1294/0188/files/11455100603.pdf
    • https://static.usrfiles.com/ugd/b8c837_09ba5eaabece408292facf589dff1e0c.pdf
    • https://static.usrfiles.com/ugd/3e0cb9_c9d5d2b93a9e471aa0690b3f2190af04.pdf
    • https://static.usrfiles.com/ugd/a467d2_eba8aee0599f4212ad93145f7a4e38c0.pdf
    • https://static.usrfiles.com/ugd/b8c837_d6247f754daa4a7dbd816da461b6224e.pdf
    • https://static.usrfiles.com/ugd/0e2875_9b8e21a5df5040ccad61e0168010ce01.pdf
    • https://cdn.shopify.com/s/files/1/0429/2929/1427/files/donibal.pdf
    • https://cdn.shopify.com/s/files/1/0434/8513/5014/files/39418082653.pdf
    • https://cdn.shopify.com/s/files/1/0435/6761/2067/files/84992505737.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_off000048fa.bin
bbf8e88dc3bec51b4a35be3ef78ae304767a92b84b1df63e7ecd3fc97cdec9e6
pdf-font-stream PDF embedded font (sfnt) at offset 0x48FA 4744 bytes
font_01_sfnt_off00005936.bin
7e5bd4892206407a939fc314fc4e044d9f6a7125c9cb40f9eec7a10de3460a82
pdf-font-stream PDF embedded font (sfnt) at offset 0x5936 10372 bytes