Malicious PDF — malware analysis report

Static analysis result for SHA-256 4af6388deefb0127…

MALICIOUS

PDF

42.4 KB Created: 2020-08-06 11:16:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 08eb27db1348bcaa45d04ef0030d194b SHA-1: dac4f26340158c7714a819fad0020f2ac833f482 SHA-256: 4af6388deefb0127232414116e62768fed60b6419ae29e5cd117e50b795e8dc2
152 Risk Score

Malware Insights

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

The PDF contains a lure text suggesting it is an application letter, but the embedded link redirects to a known malicious domain. The PDF_MALICIOUS_REDIRECTOR_LINK heuristic confirms this, and the ML classifier strongly indicates maliciousness. The document body itself is heavily obfuscated but contains the malicious URL, which is likely intended to lead the user to a phishing or malware download site.

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.ru/pify?keyword=application+letter+sample+for+civil+engineer+pdf
    • http://files.mgisalim.com/uploads/1/3/0/8/130813643/lisebaxobanuna.pdf
    • http://kawepez.lindenfestil.com/uploads/1/3/1/4/131408899/jenenawe_vamekipurijexes.pdf
    • http://files.katelyns-creations.com/uploads/1/3/1/3/131380480/b8002d72d02.pdf
    • http://files.pietjekobus.com/uploads/1/3/1/3/131382673/1ed102d.pdf
    • https://cdn.shopify.com/s/files/1/0433/0756/5214/files/pdf_splitter_portable.pdf
    • https://cdn.shopify.com/s/files/1/0437/6369/5770/files/aneurisma_aorta_abdominal.pdf
    • https://cdn.shopify.com/s/files/1/0432/9222/9787/files/83384178363.pdf
    • https://cdn.shopify.com/s/files/1/0428/5480/9759/files/ectomorph_bulking_workout.pdf
    • https://cdn.shopify.com/s/files/1/0438/2041/7181/files/sublime_text_mac.pdf
    • https://cdn.shopify.com/s/files/1/0432/8875/6384/files/12809927878.pdf
    • https://cdn.shopify.com/s/files/1/0433/1926/3397/files/lagivefesumo.pdf
    • https://cdn.shopify.com/s/files/1/0431/5480/0797/files/vabinugogokasekelojomi.pdf
    • https://cdn.shopify.com/s/files/1/0431/8475/0743/files/322055781.pdf
    • https://cdn.shopify.com/s/files/1/0435/7357/5841/files/juwenike.pdf
    • https://cdn.shopify.com/s/files/1/0433/7513/2821/files/11323324550.pdf
    • https://cdn.shopify.com/s/files/1/0431/9094/3904/files/45822474652.pdf
    • https://cdn.shopify.com/s/files/1/0434/0652/4566/files/mastering_manga_3.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_off000066ee.bin
8f402e13de5050188e7f5d92959d81b9368505dcd7db8887560d9ece1e4ce719
pdf-font-stream PDF embedded font (sfnt) at offset 0x66EE 5524 bytes
font_01_sfnt_off000079ac.bin
1ef647161eab2e1aa0dde048955cf5fa06ca3d6ba135f7884e1ddefa2304f986
pdf-font-stream PDF embedded font (sfnt) at offset 0x79AC 10236 bytes