Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac625c6b4971c99b…

MALICIOUS

PDF

49.4 KB Created: 2020-08-09 09:28:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f8dd9f8dd7ffe7d59e305e7d8ce3a174 SHA-1: dfb50e5f730f4ac783f06ba43e033eb4d4f39fdb SHA-256: ac625c6b4971c99b0e5a669e7cfa87b3767d8b791a9540fb4bf39e6105d66e4f
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by a machine learning classifier and contains a link farm of external PDF links. One of the primary links, 'https://ttraff.cc/pify?keyword=social+functions+of+law+pdf', points to a known malicious redirector. The document body, though heavily obfuscated, also contains this URL, suggesting the document's purpose is to lure users into clicking malicious links.

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=social+functions+of+law+pdf
    • http://files.hudsonartseason.com/uploads/1/3/1/4/131406800/931f4dac.pdf
    • http://files.dreamclimbthrive.com/uploads/1/3/2/6/132682974/6071502.pdf
    • http://files.mtbgus.com/uploads/1/3/0/7/130776403/wavebava_nokulasitoru_gokikinujijaru_repawufa.pdf
    • http://files.dickieskinzsc.com/uploads/1/3/1/8/131856757/nusanivub.pdf
    • https://cdn.shopify.com/s/files/1/0437/7310/0184/files/sikadexewijojemefiwe.pdf
    • https://cdn.shopify.com/s/files/1/0430/0842/6147/files/measures_of_shape_skewness_and_kurtosis.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/20597849085.pdf
    • https://cdn.shopify.com/s/files/1/0431/0863/0681/files/cub_scout_tiger_handbook_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0431/3019/2039/files/61121295968.pdf
    • https://cdn.shopify.com/s/files/1/0435/1095/6196/files/85401063767.pdf
    • https://cdn.shopify.com/s/files/1/0430/9726/0192/files/sc2_terran_builds.pdf
    • https://cdn.shopify.com/s/files/1/0431/5981/4306/files/nujefarovuderas.pdf
    • https://cdn.shopify.com/s/files/1/0430/4656/8098/files/sepemojogez.pdf
    • https://cdn.shopify.com/s/files/1/0433/6097/7048/files/rudijopabikabana.pdf
    • https://cdn.shopify.com/s/files/1/0437/7732/7265/files/tibup.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_off0000849f.bin
63ade9b0d4ce452b8cd8aebfe12e0ba1fc12f8307f2628711119007a5bdc00ed
pdf-font-stream PDF embedded font (sfnt) at offset 0x849F 5248 bytes
font_01_sfnt_off000096a8.bin
316c108280b5c97a49447e24fa13a471c448447e674a7a774f29db2c1a46e607
pdf-font-stream PDF embedded font (sfnt) at offset 0x96A8 10052 bytes