Malicious PDF — malware analysis report

Static analysis result for SHA-256 27db15e52b5bbf22…

MALICIOUS

PDF

41.9 KB Created: 2020-08-13 03:58:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f99ba8a33e48a36693b3ecd29ab0434d SHA-1: 7e4c5ac137d2140daf8209034694457542c34447 SHA-256: 27db15e52b5bbf22b59e3a075270e0d996f17a85bce84ab12eb315338f84483c
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for linking to known malicious redirector infrastructure, specifically to 'ttraff.cc'. The document body, though heavily obfuscated, contains the URL 'https://ttraff.cc/wb?keyword=bank%20exam%20syllabus%20pdf%202018', suggesting a lure related to bank exam syllabi. The presence of numerous other PDF links, many hosted on shopify.com, indicates a link farm strategy, likely to improve search engine ranking and distribute malicious content. No scripts were extracted from this sample.

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=bank%20exam%20syllabus%20pdf%202018
    • http://files.santafepest.com/uploads/1/3/1/4/131406811/02897056b3f.pdf
    • http://files.stdavidscarrmill.org/uploads/1/3/1/8/131871874/wagog_zemevopidabavo.pdf
    • http://files.islandbeautyportland.com/uploads/1/3/0/9/130969243/522dd448b29a.pdf
    • https://cdn.shopify.com/s/files/1/0428/3134/7868/files/pexepe.pdf
    • https://cdn.shopify.com/s/files/1/0429/7113/6154/files/kifepomizasara.pdf
    • https://cdn.shopify.com/s/files/1/0436/1610/8707/files/stages_of_counselling_process.pdf
    • https://cdn.shopify.com/s/files/1/0431/7852/4832/files/third_conditional_inversion_exercises.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/30151397197.pdf
    • https://cdn.shopify.com/s/files/1/0434/7386/2821/files/tipadobojobetavevavin.pdf
    • https://cdn.shopify.com/s/files/1/0434/2244/9820/files/arpack_tedavisi.pdf
    • https://cdn.shopify.com/s/files/1/0435/7675/4344/files/dezozidewutovirofola.pdf
    • https://cdn.shopify.com/s/files/1/0438/7107/6520/files/sobiruwonip.pdf
    • https://cdn.shopify.com/s/files/1/0428/8852/8035/files/senior_architect_portfolio.pdf
    • https://cdn.shopify.com/s/files/1/0440/8256/1176/files/catheter_ablation_of_cardiac_arrhythmias_huang.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_off000062e4.bin
e07e91006747c612e9b117b260511edf3d69d758500498cae0d15276d16a1bee
pdf-font-stream PDF embedded font (sfnt) at offset 0x62E4 6032 bytes
font_01_sfnt_off00007769.bin
92e0f13b3df8e53092ebaa5169c4c715a9e6323a9278b596b749a4f52cfcba43
pdf-font-stream PDF embedded font (sfnt) at offset 0x7769 10548 bytes