Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f896bd69cd18eba…

MALICIOUS

PDF

121.7 KB Created: 2021-06-30 06:14:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9d11cadae5bfc3b9237b84484b6502f6 SHA-1: 16f0938f8cbb99b1ba4fa8eaf79c7b1e8e5875b9 SHA-256: 6f896bd69cd18eba684c2ce5684ed31a0f6e1dce19794ca710389d5931e485d5
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous URLs hosted on compromised CMS uploads and disposable domains, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true purpose but reinforcing the link farm strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9721

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://busankid.com/webfiles/board/file///mojilukafetalibud.pdf
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1c8f122f3---78079868248.pdf
    • http://meruzhankhachatryan.com/app/webroot/files/file/dudubojixotubadewu.pdf
    • https://rybczewice.pl/userfiles/file/87999236429.pdf
    • https://davidfoleyinc.com/userfiles/file/nuwazuzu.pdf
    • http://ozari-ua.com/files/file/4132052147.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/ftftle19f7pgcnai5e9c5m3nhc/49400451086.pdf
    • https://eyescare.vn/app/webroot/upload/ckfinder/files/fepogaxux.pdf
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e976cc7f03---tewejilerevitonovikakete.pdf
    • http://acecaalcoy.com/userfiles/file/76214109060.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/16084b9bdd8309---41874878916.pdf
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/cgfealqjioq0521f7t4abn88l5/98364873297.pdf
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/b7b87c868edaf38886546e4ecb9e16b1/jidibu.pdf
    • https://cursosgratuitosonline.es/wp-content/plugins/super-forms/uploads/php/files/tu7nmfrr43irjfhfku08vv10rt/lawofezovutoneza.pdf
    • https://yingzhaoliuart.com/upload/file/joxonafowunemikifem.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16072e0e301876---7203320328.pdf
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/315e47e047f18cb0d02e1d61e3dd12c9/72702872952.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/c08de0da7de9ce267c2457e29f6a3e5a/75077289777.pdf
    • http://centralgiving.com/media/userfiles/file/93842309745.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160762f96a59c0---1566171543.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/651ddpgbfetai6rbfct7usaln9/wirefafofetin.pdf
    • https://anakmeong.com/contents//files/fiwejewok.pdf
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/q780odu2norud613vcj1426277/35194050577.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=meaning+of+soulful
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_006_off0001a0cb.bin
5ec352d0717fb8024c4e912ad7afe73831bb3e03edf931cbb71e9c5bea785ede
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1A0CB 28752 bytes
font_00_sfnt_off0000ff11.bin
67f2ab4955baaf46721a6d1fc0aa0d7283cfa420c391c65110a751e82997a161
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF11 12412 bytes
font_01_sfnt_off00012622.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12622 16792 bytes
font_02_sfnt_off00013e34.bin
90f9bce13f0a55f1d552feaa6ebbd291029253c154ec166e1c272036d934e58e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E34 32992 bytes
font_03_sfnt_off0001898f.bin
1e97b9b08a8633d79b469d22d98ba319b9e898b03c305621b2d1baf97775e46c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1898F 10284 bytes