Malicious PDF — malware analysis report

Static analysis result for SHA-256 6711f4837cec4fe8…

MALICIOUS

PDF

84.9 KB Created: 2021-07-09 07:57:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 549e3a62028fdd7da5650ab1bf088bee SHA-1: dce00a20a1c98995bba00cab8e7bc9226d5995c8 SHA-256: 6711f4837cec4fe8d6f16a7c58ee8f14a2bc8369eccf7ebd9d6d4a7dcb4208d1
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, many of which appear to be compromised or disposable. The presence of numerous PDF links and the use of 'utm_term' parameters suggest an attempt to manipulate search engine results or track phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://nadiadsa.org/userfiles/file/zililasoperamadis.pdf
    • http://russkiivopros.com/images/FCKeditor/file/53854700069.pdf
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/3df6nnqj1t2nbfe87ka5actml2/nibibis.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea95b50eea---96324402663.pdf
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608030e862c01---ginavowosoduw.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070b005c3737---67889549287.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160dd64ecc820e---muxisi.pdf
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606c81ed5a0de---78846752041.pdf
    • https://bomberosdenavarra.com/userfiles_nexo/files/94273979868.pdf
    • http://veterina-hrib.cz/user-uploads/files/56844026949.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16081ef0ca936e---lajidobikexafado.pdf
    • http://drwatsonsr.com/clients/2/2b/2b9a0cf27321ceab3a47fbd10bf94d34/File/gorokajunabilutup.pdf
    • http://allnatureint.com/userfiles/file/legaxamelu.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/864ac5578189f238085b87ab95a414e7/xawevoka.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/2ef36cb4dde0ee5b1ae77ca08013b23d/xafesij.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160964f1bc951d---podapen.pdf
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/a95a27b1d703a50c47ca13e3753b3a08/nekakumilut.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe62dd2ce3---78814294796.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc6e655476---5426272493.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8cdb679b78---ralukegezexivalugofotipit.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/493bd53a5e175e19fd5d729e46402278/18094819080.pdf
    • https://augsburger-dartliga.de/uploads/file/88032187526.pdf
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/ggqr4ksmkboc9lnbbc3ldqi8q5/nategepefuja.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=wells+fargo+interview+answers
    • 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_off0000e81f.bin
29fc53feede4ba12cc6471d169ef92c532dbb07d5ab6f5c06b011c85dc17e66a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE81F 17904 bytes
font_01_sfnt_off00011617.bin
2dc9d276cdbc02af1565e1cff0c3c3ee62b59677c84155734c873c3971677852
pdf-font-stream PDF embedded font (sfnt) at offset 0x11617 10536 bytes
font_02_sfnt_off00012e4c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E4C 16792 bytes