Malicious PDF — malware analysis report

Static analysis result for SHA-256 c25af42645a7bbec…

MALICIOUS

PDF

91.0 KB Created: 2021-06-30 20:27:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8f680508aa7d7c383f5b007e78c271a4 SHA-1: 4bb73b422b2d736a4fe5edf360aae7cb5673e3f3 SHA-256: c25af42645a7bbec69f523dfb9cd6be1a7d7a34686fac27ac5794a2ce3f32347
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to numerous URLs, many of which are hosted on compromised WordPress sites. The document's structure and the presence of multiple external links suggest an attempt to manipulate search engine results or redirect users to potentially harmful content. No scripts were extracted, but the overall pattern indicates a phishing or SEO poisoning attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9932

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://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16076028f0fca1---xagaxavod.pdf
    • http://to-tuong.com/media/ckfinder/files/xederenewexupuxovu.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/6b1ddc644507de464905bcc1d64eb410/76721992883.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/ngs35fipach8q7gu3oq6v5ls64/kebazenug.pdf
    • http://garmagostaran.com/Upload/file/55462405294.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d6917edff---20552792781.pdf
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/fc1338abe7ba10dac3840b00487803d0/wutasimafitik.pdf
    • http://starlightcelebre.org/clients/4/43/43e9139217482d7666ce300faf566241/File/79214589709.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609b8508844ad---dizisijafedomibidimozufe.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c87956d2146---mujekofo.pdf
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/b2ca6828554763e2ab064e6a580c4b92/kusegejeno.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b76500f49b---kejelubun.pdf
    • http://colorfulmedia.de/fotki/fotki/file/89313340216.pdf
    • http://aloeverajuice.cz/files/file/90200118589.pdf
    • https://afayl.com/userfiles/file/sizojuruverokebajiz.pdf
    • https://thefertilizergranulators.com/d/files/93312830644.pdf
    • https://jdrum-music.com/uploads/ckfiles/files/34761441246.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160863217c3ae3---34693805372.pdf
    • https://baxsporthorses.nl/userfiles/file/kejarotamadokubogutugo.pdf
    • https://bamor.org/userfiles/file/81726743121.pdf
    • https://ladangmimpi.com/contents//files/sisofulibobatan.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/93daaca46d476b73305e0131fc95854f/61934663108.pdf
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/8p7o67l73n9v0qglkvvm83sj33/22592456580.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=kaithi+tamilrockers+2019+movies+download+in+tamil
    • 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
stream_004_off00011683.bin
b43e09610a8a235bd63bb16f6f7f6feab71268560b9402c138411e725c177bdf
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x11683 16732 bytes
font_00_sfnt_off0000e3ce.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3CE 16792 bytes
font_01_sfnt_off0000fbe5.bin
a8d2d5080c87a8bbbac60374cafb78dcdf70dfa627c8914f6d82bfb2080e1e47
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE5 11332 bytes
font_03_sfnt_off00012e69.bin
5840af2ba670bf0ab2567e17b5b6fe4c0749bd81a90c22cdc80760cc130b7ba5
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E69 17400 bytes