Malicious PDF — malware analysis report

Static analysis result for SHA-256 35520e912c6c7984…

MALICIOUS

PDF

46.0 KB Created: 2020-08-23 02:23:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c7bbaeb215f140ef161314ebc09cf062 SHA-1: 531f9207abbf96bf432d24f8eb12ee486a16b044 SHA-256: 35520e912c6c79840fd21bbe3d00be40c95c5a01d1d2c423d5ba1d0ef111bd6d
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to Shopify domains, but one critical link directs to a known malicious redirector. The ML classifier strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains the text 'Changing between fractions decimals and percentages worksheets' and the malicious URL, suggesting a lure to educational content that redirects to a malicious site.

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=changing+between+fractions+decimals+and+percentages+worksheets
    • http://files.fonpape.com/uploads/1/3/1/4/131453843/4630458.pdf
    • http://fetoked.bournemouthjrc.co.uk/uploads/1/3/0/7/130776031/negijofefufufikepa.pdf
    • http://files.islandbeautyportland.com/uploads/1/3/0/9/130969243/522dd448b29a.pdf
    • http://sedox.myslickpic.com/uploads/1/3/0/8/130874063/bepaluwumegi.pdf
    • https://cdn.shopify.com/s/files/1/0429/6704/0154/files/gawojizuwuwoserenep.pdf
    • https://cdn.shopify.com/s/files/1/0432/5831/4912/files/33923278829.pdf
    • https://cdn.shopify.com/s/files/1/0433/2378/5370/files/34704216482.pdf
    • https://cdn.shopify.com/s/files/1/0433/8909/1998/files/speak_now_1.pdf
    • https://cdn.shopify.com/s/files/1/0434/0485/3406/files/garazabemaku.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/futikuzazojexopuvenewipu.pdf
    • https://cdn.shopify.com/s/files/1/0445/5740/2276/files/buziluve.pdf
    • https://cdn.shopify.com/s/files/1/0430/2585/8723/files/indira_gandhi_university_date_sheet_2019.pdf
    • https://cdn.shopify.com/s/files/1/0429/7313/5011/files/sivanamowanuwerug.pdf
    • https://cdn.shopify.com/s/files/1/0432/2403/9592/files/64371151571.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_off00007363.bin
d2202cdc93d71803574783fbdb7537d83ded77e64c4d9fb3c417806ed674baef
pdf-font-stream PDF embedded font (sfnt) at offset 0x7363 5768 bytes
font_01_sfnt_off000086e4.bin
cc23e991fcf3695f5703e5272aa75acfa74cf34324e525aa2b41c99fa3bd070e
pdf-font-stream PDF embedded font (sfnt) at offset 0x86E4 10636 bytes