Malicious PDF — malware analysis report

Static analysis result for SHA-256 57c50039ac6dc7ac…

MALICIOUS

PDF

90.8 KB Created: 2021-07-08 01:11:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: d5d6f70b1818affbadd0f68a2d992902 SHA-1: a84e3620ae929dd3488f102413c0ef0561156bd0 SHA-256: 57c50039ac6dc7ac61816fb6ab62d0385ef3eaab20340ebf49bca0b01c4e2432
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's used to redirect users to malicious sites. The PDF structure and embedded URLs are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 https://acavacecio.it/userfiles/files/gofurididub.pdf In PDF document text
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/80f6afdfabf4de8ae0d9c69819eafd1e/7434477801.pdfIn PDF document text
    • http://bloomx.com/sites/all/sites/bloomx.com/files/nazetutenexo.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac007c3160---jezulixanidoke.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/bb0dc853098c5271fa06b6ac7d81dc01/zozamapudatufawigi.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/67b11dd3572cfe5fcad48a7f42266eb2/97386274533.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/9453805166.pdfIn PDF document text
    • http://www.centralperdana.com/file/3130438195.pdfIn PDF document text
    • http://harasim.cz/uploaded/files/14106592181.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609df4ba8af73---nasotuwiweketamowek.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093cc66a1b03---97432423950.pdfIn PDF document text
    • http://nage-z.com/ckfinder/userfiles/files/71538221850.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/0d0b68f54de3e96e1eac20eda832fe57/saxulebiruwubu.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160e015c216969---mikelewurive.pdfIn PDF document text
    • http://archi1919.com/smlclub-files/file/66160257064.pdfIn PDF document text
    • http://rheumatology.instituteupload/content/file/65126043497.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5de233c5a1---furejubexa.pdfIn PDF document text
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/47d89fce952a777494843b78957655b1/77352899165.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/f0f375dc1e3fd6efe572227a581177ae/70619405845.pdfIn PDF document text
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/c5a13f3a055aecfb69410231302c279e/rilese.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce7a0b8057---xobosepofad.pdfIn PDF document text
    • http://healthywithhart.com/res/file/dapudukefetuw.pdfIn PDF document text
    • https://cupanghitam.com/contents//files/lovexemaxuv.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bf2e47cb094---kuneladipanazosati.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076748c98c83---nudejixuloj.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/kpm3gaolsql3srvgv1depai3a9/18052697807.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=what+high+school+credits+do+you+need+to+graduatePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fde7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDE7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000115f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115F9 17204 bytes
SHA-256: 7b0a1bfa9513c22520e5c591db3923a647a22f78d85dcb0ddee784d1f03c66d4
font_02_sfnt_off000142ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142AC 10856 bytes
SHA-256: ac565421bf61a329d13cb02f573e1dd9850eef2b25ca3cb4f102b61889d6c242