Malicious PDF — malware analysis report

Static analysis result for SHA-256 28a548898cb5b68d…

MALICIOUS

PDF

41.8 KB Created: 2020-08-03 18:33:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f8d47b0b9ef34ee04e30e203df50bb07 SHA-1: 047c069484131676638dd6db8f562192ac843830 SHA-256: 28a548898cb5b68da6c4185b47ee736e5ca610f9356cb8e28cb6834ed79d073f
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, which is further supported by the presence of a large number of external PDF links, indicating a link farm. The document body, though partially corrupted, contains text related to 'Adobe reader app scan to pdf' and the malicious URL, suggesting a lure to trick users into clicking the link. The ML classifier also strongly flagged this PDF as malicious.

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/pify?keyword=adobe+reader+app+scan+to+pdf
    • http://vatevagas.handwritingexplore.com/uploads/1/3/1/4/131438477/6d043.pdf
    • http://files.tennysontoss.com/uploads/1/3/1/4/131483009/sonuxuniwopiso-fumip.pdf
    • http://files.navjot-singh.com/uploads/1/3/1/3/131383377/f1996a2085.pdf
    • http://files.dental-medical-connections.com/uploads/1/3/0/9/130969768/wakitexol-zimiramujexuvov.pdf
    • https://cdn.shopify.com/s/files/1/0430/3942/4663/files/77459920402.pdf
    • https://cdn.shopify.com/s/files/1/0438/4233/8981/files/vixaposamatoxofawedekaj.pdf
    • https://cdn.shopify.com/s/files/1/0430/2195/9325/files/dimiku.pdf
    • https://cdn.shopify.com/s/files/1/0430/8454/6209/files/63701520110.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/72518400380.pdf
    • https://cdn.shopify.com/s/files/1/0435/1547/8176/files/73075384568.pdf
    • https://cdn.shopify.com/s/files/1/0428/1093/3414/files/3381338152.pdf
    • https://cdn.shopify.com/s/files/1/0430/9870/1977/files/54149516745.pdf
    • https://cdn.shopify.com/s/files/1/0427/6636/8935/files/53860390144.pdf
    • https://cdn.shopify.com/s/files/1/0437/7467/3057/files/89549214714.pdf
    • https://cdn.shopify.com/s/files/1/0433/9243/4326/files/juvupomeso.pdf
    • https://cdn.shopify.com/s/files/1/0436/5395/5742/files/54961134692.pdf
    • https://cdn.shopify.com/s/files/1/0434/2077/8653/files/99707080684.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_off00006291.bin
17e19ac01d68d8e81ba519500f6274263031a500d78ab645da5369216df6481e
pdf-font-stream PDF embedded font (sfnt) at offset 0x6291 5248 bytes
font_01_sfnt_off00007475.bin
c54ad9a6d4bbeb0088a4beec581529f1e4dc630dc1c8dd6e99c04b91401aa502
pdf-font-stream PDF embedded font (sfnt) at offset 0x7475 10764 bytes