Malicious PDF — malware analysis report

Static analysis result for SHA-256 328a24191b6fd06b…

MALICIOUS

PDF

41.8 KB Created: 2020-08-13 19:27:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 338cf07d81fac11a85ef73abdae48853 SHA-1: 4780c2069b38912441323661d87c8d8d0255a100 SHA-256: 328a24191b6fd06bdbb45e81a16fbdf6c5a26a8f263bf8560036522b6914d405
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.cc/wb?keyword=precise%20definition%20of%20a%20limit%20worksheet'. The document body also contains this URL, suggesting the primary intent is to lure the user to this malicious site. The ML classifier strongly supports the malicious nature of this PDF. No scripts were extracted, and the family is unknown.

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/wb?keyword=precise%20definition%20of%20a%20limit%20worksheet
    • http://files.prayerlifemusic.com/uploads/1/3/0/7/130776698/2c9dda4.pdf
    • http://files.claireallegrataylor.net/uploads/1/3/0/8/130813747/wizakirevibu-tunuxejomenodus.pdf
    • http://files.jcjnutrition.com/uploads/1/3/1/8/131857024/jiberagusagupetup.pdf
    • http://geraxumor.capstonelegacyscholarshipfund.com/uploads/1/3/0/7/130739873/6383141.pdf
    • https://cdn.shopify.com/s/files/1/0427/9356/6364/files/cardinalidad_de_conjuntos_ejercicios_resueltos.pdf
    • https://cdn.shopify.com/s/files/1/0430/4617/4877/files/zalabik.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/rosetotirumeza.pdf
    • https://cdn.shopify.com/s/files/1/0433/1238/2117/files/39081743097.pdf
    • https://cdn.shopify.com/s/files/1/0434/5842/9078/files/karazhan_chess_solo.pdf
    • https://cdn.shopify.com/s/files/1/0435/3743/2744/files/nijiwakofisipabof.pdf
    • https://cdn.shopify.com/s/files/1/0433/9187/7283/files/38163083242.pdf
    • https://cdn.shopify.com/s/files/1/0437/7736/0029/files/69713062179.pdf
    • https://cdn.shopify.com/s/files/1/0435/7075/7791/files/15153446276.pdf
    • https://cdn.shopify.com/s/files/1/0431/2170/5124/files/2016-_17_school_calendar_template.pdf
    • https://cdn.shopify.com/s/files/1/0434/0678/6725/files/symlet_wavelet_transform.pdf
    • https://cdn.shopify.com/s/files/1/0427/6633/6166/files/20351514453.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_off0000638a.bin
73859fb184fea9fbd70904189530d2ee200c9b28025d50085ce9dce39a7613b6
pdf-font-stream PDF embedded font (sfnt) at offset 0x638A 5416 bytes
font_01_sfnt_off000075d5.bin
b31fdf0bf36455e7bdb635f2a4320ae579aa917e9dc1d1f503e7a5ab16c629d2
pdf-font-stream PDF embedded font (sfnt) at offset 0x75D5 10616 bytes