Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4d8d482113c2a1f…

MALICIOUS

PDF

42.3 KB Created: 2020-08-25 20:11:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fd6463f56c23b68374a8133ca4a6e22e SHA-1: fb5112c7879b4325ea6187613fe630abf0d6cea3 SHA-256: a4d8d482113c2a1ff92214603d17d1643c65e95075f563afe042f8aadd9cf967
152 Risk Score

Malware Insights

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

The PDF file was flagged by multiple critical heuristics, including PDF_MALICIOUS_REDIRECTOR_LINK and PDF_SEO_LINK_FARM, indicating it contains numerous links to potentially malicious or redirector domains. The ML classifier also strongly indicated maliciousness. The document body contains the text 'Reassess your chess workbook' and numerous embedded URLs, suggesting a lure to a phishing or malware distribution 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.ru/pify?keyword=reassess+your+chess+workbook
    • http://files.glasgowscottieband.com/uploads/1/3/0/9/130969874/7544141.pdf
    • http://files.earlychildhoodchildren.com/uploads/1/3/0/7/130775475/wibokuwowunola.pdf
    • http://files.seanjonesfitness.com/uploads/1/3/0/7/130740561/rabixeto_tuveluroxuguj_finuvigejotep.pdf
    • http://gixop.ivegottheruns.org/uploads/1/3/0/8/130813840/sizigafutani.pdf
    • https://cdn.shopify.com/s/files/1/0433/4980/3166/files/zojefebunulu.pdf
    • https://cdn.shopify.com/s/files/1/0431/2750/5047/files/puvawurobexe.pdf
    • https://cdn.shopify.com/s/files/1/0435/8638/8136/files/35629077613.pdf
    • https://cdn.shopify.com/s/files/1/0440/1597/6613/files/computer_games_8_ball_pool.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/tazoxusejeko.pdf
    • https://cdn.shopify.com/s/files/1/0433/6127/1959/files/tufaxidovizeredasikovi.pdf
    • https://cdn.shopify.com/s/files/1/0437/1123/4197/files/dufezuzokubudofizileraju.pdf
    • https://cdn.shopify.com/s/files/1/0440/8626/3960/files/what_is_cracked_minecraft.pdf
    • https://cdn.shopify.com/s/files/1/0437/7529/5640/files/ffmpeg_cheat_sheet.pdf
    • https://cdn.shopify.com/s/files/1/0429/2473/6678/files/88832652241.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005f4b.bin
d4337f1b299f8acbc30aa93352ab736fb65e69101f09ef0a9796ddae3f673717
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F4B 5260 bytes
font_01_sfnt_off0000713b.bin
03efc1c6f5f175080221b6837886160dba2c716a3a908ed97b72bdd540c67807
pdf-font-stream PDF embedded font (sfnt) at offset 0x713B 1668 bytes
font_02_sfnt_off0000799e.bin
efe88d8ed82ad358ca8c92a3a983c0e86f29d64f9c556256a5f00170220e82f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x799E 10060 bytes