Malicious PDF — malware analysis report

Static analysis result for SHA-256 b27aa5612f4bcdd0…

MALICIOUS

PDF

99.2 KB Created: 2021-06-27 01:23:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 82bb588cc409ddaa2f8440b5ac5f5b68 SHA-1: ab855ef0c5f167fe88396a45355c35c15a71f913 SHA-256: b27aa5612f4bcdd0ab56bc7a0c0fe917d3156d0e90666932d5b47fa320487114
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no readable content to infer a specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9839

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://aslimitada.com/userfiles/file/dosojitudipokenemirebafes.pdf
    • https://samsungklimalar.com/upload/ckfinder/files/lamakofu.pdf
    • https://biodent.ro/m4fm_files/m4news/ck-uploads-files/40057883286.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/f4b5bf87b6053d883848766469910d40/nakuzilidagajusefereporo.pdf
    • http://aihyang.com/userfiles/file/wikarapukamigagoviginuvat.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bb1be4405af---84887590451.pdf
    • http://kfbi.ru/content/file/86974840950.pdf
    • http://temple.mo/userfiles/file/45313104137.pdf
    • http://101-games.ru/images/uploads/files/68494584418.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/1cb8vh3nk747g0hhhagq6mj5vo/53613230352.pdf
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/3vvg1lnop08009092ccdj8mbi0/29972143427.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160720462d5f1c---salepitepugefude.pdf
    • http://mxagproducts.com/upload/browse/file/mosipigatigomavoketeziget.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090a175f1491---64264239183.pdf
    • https://uniontend.com/userfiles/files/zojit.pdf
    • https://bloomeng.com/uploads/4162723627.pdf
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/4d32435f08fd02dd11d59f739b5b695d/vowabas.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a0527574317---xameti.pdf
    • http://seanmore.com/userData/board/file/pukevubolegara.pdf
    • http://novussiteyonetimi.com/uploads/file/wuzegidepijorunisigil.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160adaba982cb6---lixuxizapijifunikeloxuk.pdf
    • https://aspaeng.com/files/image/files/taxeguru.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=casa+amor+exclusive+for+ladies+full+movie+english+subtitles+download
    • 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_007_off00016204.bin
52acac7be7da9e9654129c6cb5d02be298248702114fe0ea1bf7dfd891aae096
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x16204 17960 bytes
font_00_sfnt_off0000dd6c.bin
583a1c5dcd55e5748e426ee1ff3f6430568512d58ce64f92726b8bc55ad42b3c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6C 11448 bytes
font_01_sfnt_off0000f816.bin
0d91b93c30cdb4b9fcc5287ef31e0f6d3b75050094e35c3303e90e7f2c1d387e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF816 2296 bytes
font_02_sfnt_off00010215.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10215 16792 bytes
font_03_sfnt_off00011a27.bin
693a6ac1a151d9d9a2752579713bdd4c25af5aef7ee7c61dc44cc4f2f84669f5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A27 28768 bytes