Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e3d11d8f4e23851…

MALICIOUS

PDF

88.7 KB Created: 2021-08-06 11:57:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 79f9f7900da4246a522d54bde12c71d7 SHA-1: f1acf5b8fbdc62031dec9d7f01af56cab69604c9 SHA-256: 4e3d11d8f4e23851af0239ee3d9a1387b9e3367fa3783672fe0c0f4929353746
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, with many URLs pointing to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and embedded links are consistent with attempts to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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 http://hnatiukreunion.com/clients/b/b5/b5561851e3069b632e798ef7a1275556/File/dekonekaniro.pdf
    • http://profitoolinfo.ru/ckfinder/userfiles/files/mibulufuvilomenusuk.pdf
    • http://jdjcnc.com/upfolder/e/files/20210722183427.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16091143b0095d---fobesedajisoxapoza.pdf
    • https://dukeofmarshall.com/ckfinder/userfiles/files/24592482642.pdf
    • https://abofahed.com/userfiles/file/jelisuwege.pdf
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e715f681ff4---puzokilubib.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16077b7cc0e0dc---lapodonudokuzewitaturi.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7e48a9cea---mabolapilunekupis.pdf
    • http://hoadondientu-ptp.vn/images/ckeditor/files/56943650306.pdf
    • http://jlsxjy.com/right/UploadFile/file///2021072806201873499.pdf
    • http://1night2daytour.com/ckupload/files/delutedazumipixivof.pdf
    • https://bank-kredit.at/ckfinder/userfiles/files/dagos.pdf
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160792d98dafd3---23392319.pdf
    • https://nanyangtextile.com/userfiles/file/mimuvinabur.pdf
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/9699a2f97ea1b6b8b36274e6eb340431/buluzovamipulire.pdf
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/35caddf73b29fe6df702c35d1cf15350/89823869954.pdf
    • https://areicon.com/images/file/79509924070.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610a1ccf82461---79956752895.pdf
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bde13098d98---xolutumejisibidavibur.pdf
    • https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/5092876261.pdf
    • http://brilsports.ro/userfiles/file///55209471235.pdf
    • http://ptaki.info/imgekoprojekty/files/76030288797.pdf
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/96f95203837c0ba05960b46bde1bd527/14229492764.pdf
    • http://www.sm.ac.th/ckfinder/userfiles/files/wisatesasalijik.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/5bc2c2184d3c187508424aa9e07d6cf2/nuzumetuzitedesobitegol.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=caza+venados+juego
    • 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_off0000f407.bin
7d5daf7355dee1d4504db63ac775b06e79e03bc6f178bc84aba45647620a6a55
pdf-font-stream PDF embedded font (sfnt) at offset 0xF407 18380 bytes
font_01_sfnt_off00012335.bin
a5edae1f807ec0c1fe48c48463b9b6839ccb4678e2e89e831bb4e71d43111668
pdf-font-stream PDF embedded font (sfnt) at offset 0x12335 10476 bytes
font_02_sfnt_off00013b03.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B03 16792 bytes