Malicious PDF — malware analysis report

Static analysis result for SHA-256 18aaa3c7a887a672…

MALICIOUS

PDF

83.1 KB Created: 2021-07-03 00:53:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0c77ceb1edb10a5d0cedf098bca0a00a SHA-1: dcee41e3fbfc4fb052e79355c89bc67a0ed28860 SHA-256: 18aaa3c7a887a672e0517f0c940b86b034d3172fe13b39618942e8d91ae545e5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The PDF contains numerous links to external PDF files, many hosted on domains associated with compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute further malicious content. ClamAV and ML classifiers strongly indicate maliciousness, with the primary function appearing to be directing users to potentially harmful external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://srsheicha.com/uploadfile/file/zofidesivudi.pdf
    • http://nuocmambason.com/upload/fckimagesfile/0b0ffbe58d83397b6e0eea17c1694b37.pdf
    • http://fructusartis.com/i/File/82258945493.pdf
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/b36a66bda5d8ee8f4794fa7a8016cf18/20105685847.pdf
    • http://kentcliffordreunion.com/clients/a/aa/aa84b18e55fac3ff3c25336c5005d9e5/File/kafezokota.pdf
    • https://bikidi.com/UpFiles/WebEditorFiles/file/60582147960.pdf
    • https://oriental-kitchens.com/userfiles/files/73214475762.pdf
    • http://copelandreunionla.com/clients/6/66/66f6f3de7053633686652f51c4c00696/File/sazipitum.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/c9e77d914d8b5cc33297e2aa29e8e9a0/fafivud.pdf
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac49d8cdfa4---40378787059.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607636e809188---32245395484.pdf
    • https://motelandratecuci.ro/userfiles/file/gajotaso.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/3nhamtjb39ni2884eq3lsjeh59/80967374108.pdf
    • http://www.niziointerior.pl/upload/file/30812889571.pdf
    • http://andrelandberg.com/userfiles/file/besogofepotesasoz.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/c19fec99328e3ce1800eaa7f0b6e5706/21161192613.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/d374390504101c7596d63b008dbb5e0f/99215343598.pdf
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/64360228509.pdf
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aabd5acbfe8---29086237304.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16078b6bda8b00---93299016726.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088088fb6b8b---nonabimokuduje.pdf
    • http://msslink.ru/userfiles/files/41628924569.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=we+gotta+get+away+from+here
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc33.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC33 16792 bytes
font_01_sfnt_off0000e44a.bin
9c3c21f987208b84228e0383529ee01cce3d2c20651524ff1fc5c74303a134b0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE44A 10444 bytes
font_02_sfnt_off0000fc15.bin
27fa49ca30b1f57c6e4f8b99ad1f73ead7010ce1f191e20d716503af09158f46
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC15 16160 bytes
font_03_sfnt_off0001118a.bin
d5b954e15f693c3d4e2676d710351cf4c3ed6a50908b2768588ef6743385ae92
pdf-font-stream PDF embedded font (sfnt) at offset 0x1118A 17244 bytes