Malicious PDF — malware analysis report

Static analysis result for SHA-256 a538be38d0c5b451…

MALICIOUS

PDF

44.2 KB Created: 2021-06-01 22:12:43 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 18787c0c0803e51594ce0ed859672bd3 SHA-1: 65591da937761c7e0de6c204cb67a9b151040dd6 SHA-256: a538be38d0c5b45181659f49e6023814ef1da4a4fe000d4ad7892861106e8ec2
200 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains multiple links that redirect to malicious infrastructure, masquerading as game hacks or generators. The ML classifier strongly indicated maliciousness, and the document body, though partially corrupted, contains references to 'Robux Hack Validation Code' and URLs associated with such lures. The primary attack pattern involves luring users to click on these links, likely to download further malware or engage in credential phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9865

Heuristics 5

  • PDF links to a 'free generator / game hack' redirector critical PDF_GAME_HACK_REDIRECT_LURE
    PDF's clickable action targets a redirector of the form /app/<id>/<slug>-game-hack — the landing-page shape of a large SEO 'free spins / generator / game hack' lure family that funnels victims through rotating disposable hosts to a malware/scam payload. The multi-link variants also trip ML/link-farm rules; this catches the single-link variants that otherwise score clean. CRITICAL on its own: the /app/<id>/<slug>-game-hack path shape is unambiguous scam infra, and the host rotates so a host-list match can't be relied on.
  • 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.
  • Brand-impersonation credential phishing lure high SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: call-to-action link host does not match the impersonated brand: https://netcdn.xyz/app/431946152/robux-hack-validation-code-game-hack.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://netcdn.xyz/app/431946152/robux-hack-validation-code-game-hack In PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/free-robux-exe_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/hack-roblox-free-robux-pastebin-com_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/flying-in-roblox-hack_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/minecraft-pc-free_GM479516143.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/how-to-get-minecraft-windows-10-edition-for-free_GM479516143.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/how-to-make-stuff-free-on-roblox-using-inspect_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/how-to-get-free-catalog-items-on-roblox-pastebin_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/roblox-alien-simolator-hack-script_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/roblox-robux-hack-tutorial_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/are-games-on-roblox-free-to-make_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/roblox-vehical-cheats_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/games-that-will-actually-give-you-free-robux_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/coin-master-daily-free-spins_GM406889139.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/minecraft-hack-download_GM479516143.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/roblox-hacked-com-2021_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/how-to-do-hacks-with-admin-roblox_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/roblox-hacker-roblox_GM431946152.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/minecraft-free-download-chromebook_GM479516143.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/free-tiktok-likes-trial_GM835599320.pdfIn PDF document text
    • https://vissalutis.pl/wp-content/uploads/fsqm-files/roblox-catalog-hack-2021_GM431946152.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00005197.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x5197 24060 bytes
SHA-256: c76836af37954f9186c273def1568672f936d4594e1e702c2e4fb863153e5665
font_01_sfnt_off00008845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8845 18852 bytes
SHA-256: 0099fd1b4e8d3cef27b0c3b1a159b1cd41c11ae25b5602c09befc4007e84065d