Malicious PDF — malware analysis report

Static analysis result for SHA-256 049aacfc5d596d60…

MALICIOUS

PDF

84.6 KB Created: 2021-06-25 16:50:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 05fa58f31f227c7b3e0acfaca7b5d500 SHA-1: 7599bd47afff52b78d3856f4eaa396aa01b1ce27 SHA-256: 049aacfc5d596d60fa383fea04700dea5a87666e4809d3528691f31fb305a583
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised domains or disposable hosting. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests the document's purpose is to redirect users to external, potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://buka.ru/sadm_files/39662201201.pdf In PDF document text
    • https://alianzatours.com/imagenes/file/pusipek.pdfIn PDF document text
    • http://royalrep.com/userfiles/files/54696257005.pdfIn PDF document text
    • http://ilovehikari.com/uploads/files/gitibapexalusexaze.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/xerov.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/ridoluwalubopukoraroxe.pdfIn PDF document text
    • http://happypalettebnb.com/CKEdit/upload/files/zebevorilizukibasiru.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/fi5v1i98ot8lpbukn0khg01lq8/rufatakuwuxevezoze.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bcd7fe1f23---9779483769.pdfIn PDF document text
    • https://sardavetri.it/userfiles/file/pewikuwuvobedo.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609f4a4e15c0e---toluminozefagam.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160892a9756eba---tubusufoburaruriteba.pdfIn PDF document text
    • https://angkagenap.com/contents//files/89877037272.pdfIn PDF document text
    • https://soalmatematik.com/userfiles/file/basanofamasopamuwarikikim.pdfIn PDF document text
    • http://bhavalaya.org/ckfinder/userfiles/files/25996302901.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160859c55ea197---kamolanomurinezilol.pdfIn PDF document text
    • https://foreningenflex.se/anvandarbilder/173/files/38233957265.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=subnautica+where+to+find+diamond+for+laser+cutterPDF 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_off0000e574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE574 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD8B 11144 bytes
SHA-256: 88f85ae9b4e2012ff911a4f47a603048f501ffb6f2a86e0c8a1cad0d9bc31cd2
font_02_sfnt_off0001176f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1176F 16916 bytes
SHA-256: 2b9448448ee45c87439761dc8639295f81a8b009ff2d8996fdb4e7725aee1f73