Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2f46e59e138457f…

MALICIOUS

PDF

33.5 KB Created: 2020-08-15 14:51:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0c38785051755afc97218bf0433846bc SHA-1: 6afafc138ad9c9379e38d5cd0bc04c0d648bdb65 SHA-256: a2f46e59e138457f92d9a7dfb46db34f895533b79e6f79787b2db1f86d83275a
152 Risk Score

Malware Insights

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

The PDF contains a high number of embedded links, many of which point to external resources. One critical heuristic identified a link to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains a URL that appears to be the primary lure. The ML classifier strongly indicated 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=aristotle+rhetoric+book+pdf
    • http://files.silkbridaleaston.com/uploads/1/3/2/7/132712185/vilamigipexutozem.pdf
    • http://files.lyricmgmt.com/uploads/1/3/1/4/131483108/4a6a0.pdf
    • http://files.cameronpoydras.com/uploads/1/3/0/7/130776812/jazetirizujegep.pdf
    • https://cdn.shopify.com/s/files/1/0448/5169/1681/files/umayyad_caliphate.pdf
    • https://cdn.shopify.com/s/files/1/0432/5654/5433/files/66755939063.pdf
    • https://cdn.shopify.com/s/files/1/0436/4081/5774/files/45154464519.pdf
    • https://cdn.shopify.com/s/files/1/0434/4234/0007/files/42367215477.pdf
    • https://cdn.shopify.com/s/files/1/0432/3000/3367/files/36538493957.pdf
    • https://cdn.shopify.com/s/files/1/0429/8866/7033/files/mezoguwewinovamemu.pdf
    • https://cdn.shopify.com/s/files/1/0436/1430/6466/files/biomerieux_virtuo.pdf
    • https://cdn.shopify.com/s/files/1/0434/3041/2454/files/xavavusexuxegezamuxiv.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/99289858455.pdf
    • https://cdn.shopify.com/s/files/1/0437/6897/1415/files/chrome_web_store_itunes.pdf
    • https://cdn.shopify.com/s/files/1/0438/2582/3904/files/97722339617.pdf
    • https://cdn.shopify.com/s/files/1/0436/4081/5774/files/vudeneguluseziwade.pdf
    • https://cdn.shopify.com/s/files/1/0435/3766/2103/files/41644813803.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_off00004900.bin
5a66147cd511d71a016d76a9276d116243075d58480c4bd3ca52f5ddca9559cf
pdf-font-stream PDF embedded font (sfnt) at offset 0x4900 5228 bytes
font_01_sfnt_off00005ab7.bin
78581794fc9ef5f9e1a2a0960a5d42bd52392fa8b4aa15eaf7c6bfbdd55709e0
pdf-font-stream PDF embedded font (sfnt) at offset 0x5AB7 9000 bytes