Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf7c81ba97ca53ae…

MALICIOUS

PDF

48.6 KB Created: 2020-08-30 22:49:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d12aaee6c83a547dd7beff4455f999ac SHA-1: 88bb13a1d767eadb0b6f9eff86de137e05cc52fc SHA-256: bf7c81ba97ca53ae74164ca3b88882e81b39a15957aabc5c65933513a0fa7280
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 'ttraff.com'. Additionally, it exhibits characteristics of a PDF link farm, with numerous embedded URLs, many of which are benign but serve to obscure the malicious one. The ML classifier also strongly indicated maliciousness.

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=funciones+trigonometricas+ejercicios+resueltos
    • https://static.usrfiles.com/ugd/b8c837_5dc92c6212214c899a1e276f0a8fa8fb.pdf
    • https://static.usrfiles.com/ugd/b8c837_6ceb8b81ccd44384867f06605ed506c9.pdf
    • https://static.usrfiles.com/ugd/dfb5f8_a3ed8490e94248a8994dd9ce18ec2107.pdf
    • https://static.usrfiles.com/ugd/5ed537_4f4e9b1681634d41a6fd83d0c7262e1c.pdf
    • https://static.usrfiles.com/ugd/b8c837_74beb7bea6ba4e3fb1485657d6d6f66d.pdf
    • https://cdn.shopify.com/s/files/1/0429/8512/8099/files/rise_of_the_guardians_full_movie_fre.pdf
    • https://cdn.shopify.com/s/files/1/0435/4444/5092/files/50530363370.pdf
    • https://cdn.shopify.com/s/files/1/0430/6888/3106/files/xizena.pdf
    • https://cdn.shopify.com/s/files/1/0432/3019/9966/files/5330903416.pdf
    • https://cdn.shopify.com/s/files/1/0433/7719/7221/files/civil_service_exam_questions_and_answers.pdf
    • https://static.usrfiles.com/ugd/b8c837_1638111e37bd4c80b3b30bbc8a6ccb82.pdf
    • https://static.usrfiles.com/ugd/d7ba0f_e3e58958072c433a993ee18d7fbb6d9f.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/
    • https://cdn.shopify.com/s/files/1/0433/7719/7221/files/civil_service_exam_

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000661f.bin
0825cb04819f9318b0b1b703b934367ced4d2d1c21ff3e7ed72b738e0cb605c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x661F 5152 bytes
font_01_sfnt_off0000778d.bin
37095fb445b2cd66e483eed3d32c8de83d4ec4df497e010adc705e58b1e3fd13
pdf-font-stream PDF embedded font (sfnt) at offset 0x778D 11600 bytes
font_02_sfnt_off00009dd5.bin
9bfde8731018a8dfbc0ddb83d25b488b96f65e5ac16d05014908b0c6d3aaeb94
pdf-font-stream PDF embedded font (sfnt) at offset 0x9DD5 16200 bytes