Malicious PDF — malware analysis report

Static analysis result for SHA-256 d7c75efc70797ad2…

MALICIOUS

PDF

41.2 KB Created: 2020-08-14 18:02:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cd90af5111bfbd61154f4b00500869bd SHA-1: d89cef96d4cab76a4171f7304de97873ef4759ac SHA-256: d7c75efc70797ad2a17a436e136761bc81f16df1fdb775063bfb1273676ff5e2
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to a link farm hosted on cdn.shopify.com. One critical heuristic identified a redirector link to traff.cc, which is known malicious infrastructure. The ML classifier also strongly indicated maliciousness. The document body contains text related to 'numerical reasoning test answers', likely a lure to entice users to click the embedded links.

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/pify?keyword=ey+numerical+reasoning+test+answers
    • http://files.k9compass.com/uploads/1/3/1/4/131453724/9962875.pdf
    • http://files.ramsgateswissys.com/uploads/1/3/1/4/131453818/degirax.pdf
    • http://files.goodshepherdinoshkosh.com/uploads/1/3/2/8/132815791/jamarakam_laremekim.pdf
    • http://files.summasportswear.com/uploads/1/3/1/4/131453807/118d8e22a22790b.pdf
    • http://files.victorybaptist-wf.org/uploads/1/3/1/4/131454521/pakatojetuvupedul.pdf
    • https://cdn.shopify.com/s/files/1/0440/3052/5590/files/biodegradation_book.pdf
    • https://cdn.shopify.com/s/files/1/0432/0709/8529/files/peratizesiju.pdf
    • https://cdn.shopify.com/s/files/1/0428/8118/8003/files/dofotapad.pdf
    • https://cdn.shopify.com/s/files/1/0430/9126/3649/files/california_9th_grade_math_textbook.pdf
    • https://cdn.shopify.com/s/files/1/0434/4774/6710/files/demography_and_economic_development.pdf
    • https://cdn.shopify.com/s/files/1/0438/2910/0701/files/nusojalotitebi.pdf
    • https://cdn.shopify.com/s/files/1/0431/5165/5061/files/all_about_periodic_table.pdf
    • https://cdn.shopify.com/s/files/1/0435/7432/9507/files/pat_a_cake_lyrics.pdf
    • https://cdn.shopify.com/s/files/1/0429/7631/3503/files/kanigi.pdf
    • https://cdn.shopify.com/s/files/1/0432/5369/4626/files/18367093793.pdf
    • https://cdn.shopify.com/s/files/1/0434/4214/3397/files/58743975100.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_off00006381.bin
868cd0b6ef848244e6e38e0193f6923ff3c6841df01fbfd76ae5ba6f48d8775e
pdf-font-stream PDF embedded font (sfnt) at offset 0x6381 5268 bytes
font_01_sfnt_off00007565.bin
97e90fd29b6ef86804f8ffcff4dafd9d085b6d97250abd96afe55c15a0a6eb07
pdf-font-stream PDF embedded font (sfnt) at offset 0x7565 10012 bytes