Malicious PDF — malware analysis report

Static analysis result for SHA-256 551223d19da14020…

MALICIOUS

PDF

97.0 KB Created: 2021-07-03 11:43:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6b3469c0a9652b0c2d8124ce4b38fc4e SHA-1: df8662657b60163a0e9d29853c886a24e984af7d SHA-256: 551223d19da140204491d575a7d3f7040000160d523130ad8592c3d17efb19e8
156 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting. These links likely serve as lures for phishing attacks or to distribute further malware. No scripts were extracted, but the PDF structure and URL patterns strongly suggest a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9811

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://laborke.ru/uplcv?utm_term=armoury+crate+service
    • http://fsgpj.com/upfolder/e/files/20210614214211.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160af95696d1c1---72960041811.pdf
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/16075c40fad99e---tokexijovajutakog.pdf
    • http://3suntech.com/UploadFile/file/20210701040433423.pdf
    • http://susutour.com/userfile/file/32710545133.pdf
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/75e78e8a958ee97c50f2d281bf25dd61/bomekimemopuvujo.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/ae0d62494af43ec21026a160ff8c17db/tunexexupevogevimu.pdf
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/16074fbc4efa07---sijiwe.pdf
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c5cf31693d4---vovebefexuxamomuxu.pdf
    • http://caphegiabao.com/upload/fck/file/kibob.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/4gu4aqnhv0b5qfec6ktl5fa703/64373880963.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da997bb3352---sojebivijozananumuwom.pdf
    • http://cristal-in.fr/userfiles/file/levetonefilofinewe.pdf
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4d6e412781---narerasogimidanumivufajo.pdf
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/g41to0dko7q5ipe9jrp25eb2t6/gujojo.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607de8ad7cfae---fuseg.pdf
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b2850c9e760---43345136146.pdf
    • http://maxtarget.by/ckfinder/userfiles/files/5890517498.pdf
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608967885958a---visitejobiretigej.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608d239622165---60730506329.pdf
    • http://sjhrz.com/images/upload/File/43764075897.pdf
    • http://jjkxmy.com/upload/files/202106222300284517.pdf
    • https://artbynela.com/uploads/file/36404412880.pdf
    • http://brenno-tojestto.pl/userfiles/file/betorunimukenadawepavitof.pdf
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/ficku1tlo3m48mfpf1r8ioetr7/97025536799.pdf
    • 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
font_00_sfnt_off0000f546.bin
924645934ed2ee372d6ab87135fffbd86f6e6c7c771765dc390a8aa87584978b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF546 10500 bytes
font_01_sfnt_off00010d51.bin
649555a43cf1a87a20afaad28a6a06c2828108a09991283ea91d2f89fef04ae5
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D51 16220 bytes
font_02_sfnt_off0001231e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1231E 16792 bytes
font_03_sfnt_off00013b2b.bin
3f1748778f03e7b7e2d3a6c88ca15ef060a02f224cd71155e662fde9dd4c56c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B2B 1672 bytes
font_04_sfnt_off00014319.bin
b374da345257d7467170a0ff76f34c9b8b6e1a2adb0e12ec2dbc000f231bf8e7
pdf-font-stream PDF embedded font (sfnt) at offset 0x14319 19060 bytes