Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b21a4ccd7b9d7a5…

MALICIOUS

PDF

45.2 KB Created: 2020-08-22 18:58:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f9e108db4674bd4c9ce1254de4c0573d SHA-1: aff58178806c0db33792b8b7ba0a9c09f3d39549 SHA-256: 2b21a4ccd7b9d7a52f0a2ec03af4b5b991d3f800e9d972d121f7df198cde1af2
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one identified as a known malicious redirector. The heuristic PDF_SEO_LINK_FARM indicates a link farm structure, suggesting the primary purpose is to distribute malicious links. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, but the extensive link farm points to a delivery mechanism for further malicious content.

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/pify?keyword=alif+laila+serial
    • http://files.mrohagan.com/uploads/1/3/0/9/130969893/f665b5a59ea.pdf
    • https://cdn.shopify.com/s/files/1/0437/8663/3377/files/starbound_game_free.pdf
    • https://cdn.shopify.com/s/files/1/0431/7836/0987/files/88909268271.pdf
    • https://cdn.shopify.com/s/files/1/0432/3124/8541/files/46475034483.pdf
    • https://cdn.shopify.com/s/files/1/0433/7418/2563/files/microsoft_space_simulator.pdf
    • https://cdn.shopify.com/s/files/1/0431/5168/7848/files/intellij_format_json_single_line.pdf
    • https://cdn.shopify.com/s/files/1/0440/0565/4678/files/sinhala_bana_katha.pdf
    • https://cdn.shopify.com/s/files/1/0436/9504/6811/files/71091447145.pdf
    • https://cdn.shopify.com/s/files/1/0430/6190/3517/files/30513036001.pdf
    • https://cdn.shopify.com/s/files/1/0430/8526/7097/files/sujawowo.pdf
    • https://cdn.shopify.com/s/files/1/0433/6582/6719/files/pobisodubupudoradobetonot.pdf
    • https://cdn.shopify.com/s/files/1/0431/4673/9866/files/toxafolo.pdf
    • https://cdn.shopify.com/s/files/1/0432/3419/7666/files/network_monitoring_for_dummies_solarwinds.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005cef.bin
31be179c5702819e18ef210b18dde989c2c4184b8a1999696bf6c691bc5ff3ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x5CEF 4748 bytes
font_01_sfnt_off00006d1b.bin
fe183ab332172ffc549e9fceff28f9fbe06d78af448b357e06dac0661cd9db89
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D1B 10364 bytes
font_02_sfnt_off0000906c.bin
1517b8c3032c2e8e576cfbd77e7479d7dd0d9b1b74bd87b9f03b8584264c575b
pdf-font-stream PDF embedded font (sfnt) at offset 0x906C 16868 bytes