Malicious PDF — malware analysis report

Static analysis result for SHA-256 496bf20aceae90b2…

MALICIOUS

PDF

87.4 KB Created: 2021-07-15 10:50:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5c9a31cb742fb71a9960cdad5e09d356 SHA-1: b13dc2d3ed2b955452a1d0c2e52df06aa1839db0 SHA-256: 496bf20aceae90b2daa2714a1f94b2b486af8865ac7bd8287202a7d8cdf13cea
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed for malicious redirection. The ClamAV detection and ML classifier strongly suggest a malicious intent, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://zuche0551.com/upload/file/dizokexiniji.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a8fcc03919a---90267343845.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160868843c5a0f---walaripawivir.pdf
    • http://k-souz.com/userfiles/file/44391407849.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5b599d9c7c7ac8ed76557402bed5712d/dilukajimugabi.pdf
    • http://childconnect.com/swi/fckfiles//file/didovadojo.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1609c3c436475d---51908644515.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160c0ba8028094---50609188662.pdf
    • http://mlight.cz/archiv/file/vekibe.pdf
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160924fb8ea65f---98740707860.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160791ade4bf0f---7292274161.pdf
    • http://yogo110.com/userfiles/file/jagulot.pdf
    • http://geyikkimya.com/userfiles/upload/file/nefog.pdf
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1d28b13823---xozilalidukugaxamufipu.pdf
    • http://joy05.com/_UploadFile/Images/file/relalidisud.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/8d8e032edc9bcc17b2c5efab86f21a54/dofojesumadunona.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16089c1045e33a---fomuxisaluduvunam.pdf
    • http://duonglaohanoi.com/userfiles/file/52296921375.pdf
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608030cfd7040---12388333567.pdf
    • https://aspaeng.com/files/image/files/80745472835.pdf
    • http://rheinmotel.com/userfiles/file/98512081787.pdf
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/tso9v96tf7ngspr4ga9vp89rr3/gapijimolamulelularaduz.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=look+like+the+innocent+flower+but+be+the+serpent+under+it+literary+device
    • 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/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f010.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF010 16792 bytes
font_01_sfnt_off00010822.bin
692b35500ed3915ae360cc4a3cb899b9a3512c350e0bc570d3fc120ad739c816
pdf-font-stream PDF embedded font (sfnt) at offset 0x10822 17632 bytes
font_02_sfnt_off00013598.bin
bfa3ed9b59651be5670217f2ca7ccb66bf80991655c66a7af2ee48319188ede3
pdf-font-stream PDF embedded font (sfnt) at offset 0x13598 11272 bytes