Malicious PDF — malware analysis report

Static analysis result for SHA-256 f836b26a9a74d198…

MALICIOUS

PDF

43.3 KB Created: 2020-07-29 05:56:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1348762ef264ed7b9ac1c91bf48fd69d SHA-1: 6f0d58e7e78b825e689de20afe1703358ac835ae SHA-256: f836b26a9a74d1986fcb6d889cc9d0dc4cc76ce1a27af864fbb517f197484e57
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains numerous links to external websites, with at least one identified as a malicious redirector. The document body, though heavily obfuscated, suggests a lure related to educational worksheets. The presence of a malicious redirector and a link farm indicates an attempt to drive traffic to potentially harmful sites, likely for phishing or malware distribution. No scripts were extracted, limiting the analysis of direct payload execution.

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=reading+comprehension+for+1st+grade+worksheets
    • http://files.syvma.com/uploads/1/3/1/6/131606011/jepufugiga-misibuzulixa-mogibogadiwamor.pdf
    • http://files.naturalhealthclinicni.com/uploads/1/3/0/8/130874382/9379584.pdf
    • http://files.holisticblessingsoflove.com/uploads/1/3/1/8/131871823/ridazibule-dofoxivur.pdf
    • http://files.syvma.com/uploads/1/3/1/6/131606011/jepufugiga-misibuzulixa-mogibo
    • https://cdn.shopify.com/s/files/1/0439/8707/5230/files/pajajipujimomapiwemeduv.pdf
    • https://cdn.shopify.com/s/files/1/0428/1656/9500/files/23189439224.pdf
    • https://cdn.shopify.com/s/files/1/0435/6138/6147/files/nelax.pdf
    • https://cdn.shopify.com/s/files/1/0431/4903/3640/files/57013293877.pdf
    • https://cdn.shopify.com/s/files/1/0431/5394/8836/files/nunoboburomuvep.pdf
    • https://cdn.shopify.com/s/files/1/0437/7732/7265/files/vetutifoxavo.pdf
    • https://cdn.shopify.com/s/files/1/0433/9066/4860/files/91463481427.pdf
    • https://cdn.shopify.com/s/files/1/0433/3142/0314/files/88726122633.pdf
    • https://cdn.shopify.com/s/files/1/0434/1547/0245/files/66771323004.pdf
    • https://cdn.shopify.com/s/files/1/0431/9825/1165/files/85322483469.pdf
    • https://cdn.shopify.com/s/files/1/0428/1214/5823/files/sixovexozimunaji.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_off00006ae0.bin
c76796e07b20ec64b205dd7f75077c56ba350a688b988411e4248497674e4dbd
pdf-font-stream PDF embedded font (sfnt) at offset 0x6AE0 5540 bytes
font_01_sfnt_off00007d9b.bin
aad3ec84cf10f458be403e492ad65b25a8ca22dba3641b6a976616a4adf1bc1a
pdf-font-stream PDF embedded font (sfnt) at offset 0x7D9B 10072 bytes