Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ef544b6376198ae…

MALICIOUS

PDF

109.4 KB Created: 2020-08-20 06:13:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2a537b285bafcb7853fecf107e969e1e SHA-1: dfddbce08dd06970b96e08e3583ea4997a7ccbac SHA-256: 4ef544b6376198ae8a2674b8d88011b65e7f4d88b0e6814f0d413de1a36462e1
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains embedded links, one of which, 'https://ttraff.com/pify?keyword=bunch+of+thoughts+in+tamil+pdf', is flagged as a malicious redirector. The document body, though heavily obfuscated, contains this URL and text suggesting a lure related to a Tamil PDF. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' confirms the malicious nature of the redirector. The ML classifier also strongly indicates 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/pify?keyword=bunch+of+thoughts+in+tamil+pdf
    • http://merodotar.lawrence-writer.com/uploads/1/3/1/4/131407406/55e6a.pdf
    • https://cdn.shopify.com/s/files/1/0440/5365/9798/files/93443236409.pdf
    • https://cdn.shopify.com/s/files/1/0440/7338/6136/files/lipid_structure_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0440/6401/4486/files/puget_sound_premier_league.pdf
    • https://cdn.shopify.com/s/files/1/0435/3146/8951/files/bottle_capping_machine.pdf
    • https://cdn.shopify.com/s/files/1/0431/0515/7284/files/52902227897.pdf
    • https://cdn.shopify.com/s/files/1/0438/6953/6411/files/best_ds_emulator.pdf
    • https://cdn.shopify.com/s/files/1/0427/9785/8972/files/autodwg_dwg_to_converter_2020_crack.pdf
    • https://cdn.shopify.com/s/files/1/0431/0489/5143/files/20324194650.pdf
    • https://cdn.shopify.com/s/files/1/0434/2064/7576/files/having_a_coke_with_you_poem.pdf
    • https://cdn.shopify.com/s/files/1/0435/8547/0627/files/bosagapubemutivozukolu.pdf
    • https://cdn.shopify.com/s/files/1/0432/4196/3683/files/thank_you_note_template_for_students.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_off0001721b.bin
269664727241fedf8684d0286dbd9499fff1e599080edc4f72cf556530723233
pdf-font-stream PDF embedded font (sfnt) at offset 0x1721B 5524 bytes
font_01_sfnt_off000184c5.bin
7738bcb3fea91580d8cc62d2e0cefb2dc4b94b6c28f2b02291ed6d6cda79482e
pdf-font-stream PDF embedded font (sfnt) at offset 0x184C5 10420 bytes