Malicious PDF — malware analysis report

Static analysis result for SHA-256 a112c878a40e2c33…

MALICIOUS

PDF

46.9 KB Created: 2020-08-14 00:46:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fa0522ed5f7cff56ed709873871b6b22 SHA-1: 9a3daaa659878f406801155d35a45f23fcf7b028 SHA-256: a112c878a40e2c3303c5f6d8f11939562c7977b8979cde739684c3beb9a9f6c7
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one identified as a known malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.ru/pify?keyword=hardest+logic+questions+with+answers+tagalog', suggesting a lure to a malicious site. The presence of a large number of external PDF links also indicates a link farm, likely for SEO manipulation or to host further malicious content. The ML classifier 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.ru/pify?keyword=hardest+logic+questions+with+answers+tagalog
    • http://files.nvclbaseball.org/uploads/1/3/1/3/131383586/7005378.pdf
    • http://files.theeclecticcats.com/uploads/1/3/1/6/131637325/fced1db.pdf
    • http://files.verduemedia.com/uploads/1/3/1/8/131856353/sujaxawudalanobomo.pdf
    • http://detajak.designerpaws.org/uploads/1/3/2/8/132815002/fogowujego-raribafeso-viwiwedijezex.pdf
    • https://cdn.shopify.com/s/files/1/0430/8379/2548/files/recommendation_letter_download.pdf
    • https://cdn.shopify.com/s/files/1/0437/5363/5989/files/sifigo.pdf
    • https://cdn.shopify.com/s/files/1/0437/9725/0205/files/7381225000.pdf
    • https://cdn.shopify.com/s/files/1/0428/0903/2863/files/jatapigagazupixuxiti.pdf
    • https://cdn.shopify.com/s/files/1/0434/2359/6711/files/12119105980.pdf
    • https://cdn.shopify.com/s/files/1/0429/6556/5589/files/guxiwup.pdf
    • https://cdn.shopify.com/s/files/1/0437/0720/3739/files/65461462492.pdf
    • https://cdn.shopify.com/s/files/1/0436/1669/8526/files/52971330870.pdf
    • https://cdn.shopify.com/s/files/1/0437/0802/2938/files/92538083653.pdf
    • https://cdn.shopify.com/s/files/1/0430/8048/2970/files/kegedi.pdf
    • https://cdn.shopify.com/s/files/1/0447/1940/7257/files/2020_uae_calendar_with_holidays.pdf
    • https://cdn.shopify.com/s/files/1/0435/0722/0644/files/3520160303.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_off00007939.bin
1e8fbf7f105349ec12d73dd9abc5f98f245aa26f70bc11b6e2d6ae02e46f65b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x7939 5380 bytes
font_01_sfnt_off00008b80.bin
d5ed7674ae7df98001f8ace4ef76a33ab0d948034a961fb5ce029e7997079105
pdf-font-stream PDF embedded font (sfnt) at offset 0x8B80 10168 bytes